All titles of the first season are quotes from ''[[On the Origin of Species]]'' by [[Charles Darwin]].<ref name="quotes1">{{cite web |url=http://www.huffingtonpost.ca/2014/01/27/orphan-black-season-2_n_4674087.html |title='Orphan Black' Season 2: First Episode Title Revealed (EXCLUSIVE) |work=The Huffington Post |first=Chris |last=Jancelewicz |date=January 27, 2014 |accessdate=January 27, 2014}}</ref>

{{Episode list

|EpisodeNumber = 1

|WrittenBy = [[Graeme Manson]]

|OriginalAirDate = {{Start date|2013|3|30}}

|Viewers = 0.684<ref>{{cite web|url=http://tvbythenumbers.zap2it.com/2013/04/02/supernatural-saturday-line-up-of-doctor-who-orphan-black-the-nerdist-delivers-strong-ratings-for-bbc-america/176152|title=Supernatural Saturday Line-Up of 'Doctor Who', 'Orphan Black', & 'The Nerdist' Delivers Strong Ratings for BBC America|publisher=TV by the Numbers|first=Sara|last=Bibel|date=April 2, 2013|accessdate=April 4, 2013}}</ref>

|ShortSummary = British punk con artist Sarah Manning sees an identical woman, Beth Childs, kill herself by jumping in front of a train. Sarah retrieves Beth's bag, and finding that she is well-off, decides to take her place, and clean out Beth's bank account so she (Sarah) can collect her daughter Kira from her foster mother, Siobhan Sadler, whom Sarah calls Mrs. S. Sarah asks her foster brother Felix Dawkins to identify Beth's body as Sarah's to buy time for her scheme, and throw her drug-dealer boyfriend Victor Schmidt off her trail. Sarah withdraws $75,000 from Beth's account, but discovers to her dismay that Beth is a police detective suspended for shooting Maggie Chen. Beth's partner Arthur Bell ('Art') follows 'Beth', and breaks into her car. Sarah is approached by Katja Obinger, another lookalike from Germany. Katja is killed by a sniper, but Sarah manages to escape.

|WrittenBy = Graeme Manson

|OriginalAirDate = {{Start date|2013|4|6}}

|Viewers = 0.409<ref name="Season1">{{cite web|url=https://disqus.com/home/discussion/tvmi/thursday_final_nationals_modest_ratings_for_8216the_astronaut_wives_club8217_prime_time_golf_and_821/#comment-2089231693|title=Thursday Final Nationals: Modest Ratings for ‘The Astronaut Wives Club’, Prime Time Golf and ‘Complications’|last=Pucci|first=Douglas|work=TV Media Insights|date=June 19, 2015|accessdate=June 20, 2015}}</ref>

|ShortSummary = Sarah is contacted by a woman who instructs her to dispose of Katja's body, and retrieve her briefcase. Art tells Sarah that he has the $75,000, and won't return it until she testifies at the inquest into Maggie Chen's shooting, and clears her name. It seems that Art placed a cellphone in the hand of the dead Maggie Chen to make it look like Beth had shot Maggie in self-defence, and he doesn't want this to get out. Sarah poses as Katja to get her briefcase from the hotel. Inside the briefcase, she finds evidence of more lookalikes, one of whom is Alison Hendrix, a [[soccer mom]]. Sarah gets Alison to set up a meeting where she meets yet another lookalike, [[evolutionary developmental biology]] student Cosima Niehaus, the woman she spoke with on the phone.

|WrittenBy = Graeme Manson

|OriginalAirDate = {{Start date|2013|4|13}}

|Viewers = 0.350<ref name="Season1"/>

|ShortSummary = Alison tells Sarah that they are clones. In the briefcase, Sarah and Felix find that three of the clones Katja had found were already dead. Sarah goes to the police station to ask Art for the money back, only to be reinstated as a police detective, and drafted to cover Katja's murder. Worried that her fingerprints might be identical to Katja's she deletes them from the record. Art and Sarah track down the killer who starts shooting at them. Sarah saves Art's life, and then gives chase, only to find that the killer is another clone, Helena, a Ukrainian. Sarah stabs Helena, but Helena escapes. Art returns the money to Sarah, who gives it back to Alison, who had provided it to Beth to help with her investigation into their situation.

|WrittenBy = [[Karen Walton]]

|OriginalAirDate = {{Start date|2013|4|20}}

|Viewers = 0.361<ref name="Season1"/>

|ShortSummary = Sarah and Art continue looking for the killer, while Sarah tries to cover up that both killer and victim are her sister clones. The police believe that the killer is a [[Christian fundamentalism|fundamentalist Christian]], while Cosima deduces that the group affiliated with Helena believe the clones are abominations and must be killed. Helena keeps a close eye on Sarah and the case, putting Sarah's cover in jeopardy. Mrs. S allows her to visit Kira, but because Sarah is busy working the case, Felix asks Alison to impersonate Sarah otherwise Mrs. S would never allow her to see Kira again. However, Alison is shocked to find that Kira knows she is not Sarah. Helena lures Sarah to Maggie Chen's apartment, where it is revealed that Maggie worked for the same group Helena works for; Beth actually killed Maggie to protect the clones. Sarah allows Helena to escape before Art arrives, and Sarah quits the police force. Helena collapses and gets picked up by a man wearing the same symbol as Helena and Maggie.

|WrittenBy = Alex Levine

|OriginalAirDate = {{Start date|2013|4|27}}

|Viewers = 0.327<ref name="Season1"/>

|ShortSummary = After waking up from a supposed dream where she was experimented on, Sarah spits out an electrode from her mouth. The clones soon learn that they have monitors, people in their lives whose purpose it is to observe them. Sarah suspects Beth's boyfriend Paul Dierden of being her monitor, while Alison suspects her husband Donnie. Meanwhile, Vic comes across a chance meeting with Alison, and discovers that Sarah faked her death. In response, Sarah pays Vic $20,000 to leave her alone, 15,000 to pay for his debts incurred by her theft and 5,000 to pay for his 'pain and suffering' due to the loss of his finger over the unpaid debts. Sarah and Felix spy on Paul's work place, but unknown to them, Paul follows Sarah walking Kira home from school. Paul also discovers that "Beth's" scar is gone. After calling Sarah to meet him at their home, Paul holds Sarah at gunpoint and demands an explanation, prompting Sarah to tell him that Beth is dead. When Sarah asks Paul why he is monitoring her, Paul admits that he does not know.

|WrittenBy = Will Pascoe

|OriginalAirDate = {{Start date|2013|5|4}}

|Viewers = 0.340<ref>{{Cite web|url=http://www.showbuzzdaily.com/articles/the-skeds-friday-monday-cable-scorecard-53-613.html|title=THE SKED’S Friday-Monday Cable Scorecard – 5/3-6/13|publisher=Showbuzz Daily|first=Mitch|last=Salem|date=May 7, 2013|accessdate=April 28, 2015}}</ref>

|ShortSummary = Alison purchases a [[nanny cam]] and finds that Donnie snuck out during the middle of the night. Paranoid, Alison ties him up, while also handling a house party featuring her neighborhood. Sarah impersonates Alison to question Donnie, who says he was covering up letters from a girl he dated when he and Alison were broken up. Paul follows Sarah and ultimately learns of their nature as clones. He also helps Sarah get rid of Vic when he continues to be a nuisance to her. Felix suspects Alison's neighbor, Aynsley Norris ([[Natalie Lisinska]]), of being the actual monitor. Meanwhile, Cosima is approached by Delphine Cormier, a fellow student. Cosima suspects Delphine of being her monitor, but goes with her to a lecture given by Dr. Aldous Leekie of the Dyad Institute, a proponent of "neolution" (using technology to advance [[human evolution]]). Later, it is revealed that Delphine and Leekie are lovers.

|WrittenBy = Tony Elliott

|OriginalAirDate = {{Start date|2013|5|11}}

|Viewers = 0.280<ref name="Season1"/>

|ShortSummary = Paul is questioned by his handler, Olivier Duval regarding Beth's behavior. Though Paul tries to cover up the fact that Sarah is posing as Beth, the neolutionists discover the truth after checking the test results from experimenting on her. The neolutionists also believe Sarah to be the killer of the other clones. Meanwhile, Helena is nursed back to health by her trainer Tomas, who orders her to kill Sarah. Although she appears reluctant to do so, she implores Sarah to reveal the names of other clones. Later, Sarah calls Helena to help free Paul who is imprisoned in Olivier's nightclub, called "Neolution." Paul and Sarah hide out in Felix's loft to avoid the neolutionists. The police continue to investigate Katja's body and are perplexed to find a DNA match between the body and the killer, and that Katja's fingerprints also match Beth's.

|WrittenBy = Karen Walton

|OriginalAirDate = {{Start date|2013|5|18}}

|Viewers = 0.367<ref name="Season1"/>

|ShortSummary = Paul blackmails Olivier into telling Leekie that there was only one clone who attacked, Helena. Leekie tells Paul he has a new job for him, and then arranges for Olivier to be killed. Delphine tells Leekie that Cosima made a pass at her, and he pushes Delphine to find out how many clones Cosima has had contact with. Cosima and Delphine sleep together, and then Delphine spies on her, giving the names of the clones to Leekie, but neglecting to mention Kira. Art goes to the morgue to check 'Sarah's' body, and this leads him to Felix. They question Felix, and realize that he is the one who made an anonymous call to Art with information about Beth. Alison takes vengeance on Aynsley whom she suspects of being her monitor by having sex with her husband Chad. Aynsley finds out, and confronts Alison, and the two fight. Sarah introduces Alison to Mrs. S and tells her about the clones. While they are talking, Kira finds Helena at the front door, and follows her out into the street. Kira is very kind to Helena, but when she hears her mother call, Kira goes to find her, and gets hit by a car.

|WrittenBy = Alex Levine

|OriginalAirDate = {{Start date|2013|5|25}}

|Viewers = 0.253<ref name="Season1"/>

|ShortSummary = Kira is taken to the hospital, where it appears that she has accelerated healing. Alison returns home to find that Aynsley is holding an [[Intervention (counseling)|intervention]] regarding her past behavior and addictions, where under Felix's encouragement, Alison turns the tables by scrutinizing Aynsley. Art finds CCTV footage of the train station where Beth committed suicide, and discovers that Sarah has been impersonating her. Cosima learns that Delphine leaked the names of the clones to Leekie, and confronts her. Delphine reveals that she knows about Kira's existence but decided not to tell Leekie, knowing her life could come in danger should he know (Kira is the only known biological child of a clone). Sarah meets with Leekie, who wants her to save Helena from the Proletheans, the extremists who indoctrinated her. Tomas punished Helena for defying orders, but she is later rescued by Sarah, and turns against Tomas. They later return to Mrs. S, who has reached her contacts in England, and meet with Amelia, Sarah's birth mother. Amelia reveals that she gave her away and fled after realizing she was a [[Surrogacy|surrogate mother]] to Dyad scientists. Furthermore, Amelia gave birth to twins; Helena is Sarah's twin sister.

|WrittenBy = Graeme Manson

|OriginalAirDate = {{Start date|2013|6|1}}

|Viewers = 0.376<ref name="TVLine"/>

|ShortSummary = As Amelia meets Helena, police arrive to arrest Sarah, while Helena escapes. Sarah is about to tell Art the whole story, but gets spirited away by Daniel Rosen, a Dyad operative. Sarah is brought to Rachel Duncan, a clone who is high in the Dyad organization, who offers Sarah and Kira protection. Leekie also offers the same to Alison and Cosima, as Cosima begins to display symptoms of a respiratory illness that Katja had. Alison confronts Aynsley a final time, ending with Alison watching Aynsley accidentally choke to death on her own scarf. Amelia tells a woman pretending to be Sarah that Mrs. S is not who she says she is, but this 'Sarah' is actually Helena, who stabs Amelia, blaming her for turning her over to the Proletheans. When Sarah finds her body, she shoots Helena. Alison signs Leekie's document, while Sarah goes to meet Rachel, planning to sign as well. However on the way, Cosima and Delphine decipher a code inside the clone [[genome]]; "this organism and derivative genetic material is restricted intellectual property." Cosima warns Sarah, who leaves Dyad without signing the contract. She returns to discover Mrs. S's home ransacked, and Kira and Mrs. S gone.

All titles of the second season are quotes from the works of [[Sir Francis Bacon]].<ref name="quotes1"/>

{{Episode list

|EpisodeNumber = 11

|WrittenBy = [[Graeme Manson]]

|OriginalAirDate = {{Start date|2014|4|19}}

|Viewers = 0.620<ref name="TVLine">{{Cite web|url=http://tvline.com/2014/04/21/ratings-orphan-black-season-2-premiere-salem-wgn-america/|title=Ratings: ''Orphan Black'' Returns to Demo High, ''Salem'' Conjures Solid Numbers|publisher=TVLine|first=Matt Webb|last=Mitovich|date=April 21, 2014|accessdate=April 21, 2014}}</ref>

|ShortSummary = Sarah runs to a nearby diner, where she is quickly confronted by two armed men, one of whom is Mark Rollins, who attempt to bring her in. They kill the diner's owner (who shoots one of the men in the process), but Sarah manages to escape. She finds Felix and gets Alison to give them access to an unregistered gun so she could get Rachel to bring her to Kira and Mrs. S, as she believes Dyad has kidnapped them. Sarah impersonates Cosima at Dyad to steal Leekie's passkey and confronts Rachel, who reveals she does not have Kira. Alison, who tries to kick her addiction to pills, is chosen as the lead in the community musical replacing the now dead Aynsley. Leekie wants Cosima to start working for Dyad. With nowhere else to go for help, Sarah goes to Art's home with the intention of telling her whole story. Art, who is investigating the diner shooting, identifies the perpetrators as Proletheans; they are likely the ones who have Kira. Meanwhile, a wounded Helena stumbles into a hospital.

|WrittenBy = [[Karen Walton]] & Graeme Manson

|OriginalAirDate = {{Start date|2014|4|26}}

|Viewers = 0.718<ref>{{Cite web|url=http://www.thefutoncritic.com/ratings/2014/04/29/saturdays-cable-ratings-and-broadcast-finals-nascar-nba-playoffs-top-charts-960214/cable_20140426/|title=Saturday's Cable Ratings & Broadcast Finals: NASCAR, NBA Playoffs Top Charts|publisher=The Futon Critic|date=April 29, 2014|accessdate=May 2, 2014}}</ref>

|ShortSummary = Kira calls Sarah, and Art traces it to a motel. Sarah gets kidnapped, while Art has a run-in with Daniel, later resulting in his suspension. Sarah is taken to Mrs. S, who reveals she ran away with Kira and made it look like a kidnap. They go to a country house owned by two compatriots. Later at night, Kira admits she no longer trusts Mrs. S, so she and Sarah attempt to escape. Mrs. S learns that her compatriots plan to sell Kira to the Proletheans; she kills the two to allow Kira and Sarah to escape. Meanwhile, during Aynsley's funeral, Alison begins to suspect that Donnie was her monitor all along, so she and Felix set a trap for him, confirming her suspicions. Alison returns to drinking from the guilt of Aynsley's death. Cosima and Delphine set up a new lab at the Dyad institute to learn more about the former's condition. Art's partner Angela Deangelis learns of Helena's existence, but when she visits the hospital, Mark takes Helena away to a ranch owned by Henrik Johanssen, the Prolethean leader who plans to use Helena to create a baby. Henrik then has Tomas killed for objecting.

|WrittenBy = Alex Levine

|OriginalAirDate = {{Start date|2014|5|3}}

|Viewers = 0.450<ref>{{cite web|url=http://www.tvtango.com/series/orphan_black/episodes|title=Episode List: Orphan Black|publisher=TV Tango|accessdate=April 28, 2015}}</ref>

|ShortSummary = Sarah, Felix and Kira arrive at a house belonging to Cal Morrison, who is revealed to be one of Sarah's marks and Kira's father. He allows the three to stay for a little while. Felix returns to the city to support Alison in her play. Angela tries, and fails, to befriend Alison to learn more about the lookalikes. Before the debut, Alison drinks too much and then falls off the stage during her performance. Cosima and Delphine investigate the death of Jennifer Fitzsimmons, a clone who died from the same respiratory illness as Katja and Cosima. They autopsy the body and believe that the illness is possibly linked to the clones' infertility. Art begins to surveil Henrik's ranch, as Henrik [[marriage|marries]] Helena, then takes her away to a room. Daniel, who spent the episode looking for Sarah, tracks her down and kidnaps her, while also murdering a local police officer. Cal finds them, and he crashes his truck into their car.

|WrittenBy = [[Russ Cochrane]]

|OriginalAirDate = {{Start date|2014|5|10}}

|Viewers = 0.484<ref>{{Cite web|url=http://www.thefutoncritic.com/ratings/2014/05/13/saturdays-cable-ratings-and-broadcast-finals-nascar-nba-playoffs-claim-top-spots-268412/cable_20140510/|title=Saturday's Cable Ratings & Broadcast Finals: NASCAR, NBA Playoffs Claim Top Spots|publisher=The Futon Critic|date=May 13, 2014|accessdate=May 14, 2014}}</ref>

|ShortSummary = Cal and Sarah hide the car and the assumed dead Daniel. Sarah leaves Kira with Cal and returns to Mrs. S's home with Felix, where they find news clippings of Susan and Ethan Duncan, the founders of Leda, the cloning project, and Rachel's adoptive parents. Mrs. S, meanwhile, reunites with Carlton Redding, who helped smuggle her and Sarah out of London. Helena escapes from the ranch after Henrik's daughter Gracie tries to kill her, and remembers that Henrik took something from her. Alison wakes up in [[Drug rehabilitation|rehab]]. She is told by Donnie that she will not see her children unless she stays a week. Sarah sneaks into Rachel's apartment, only to be captured by the very much alive Daniel. As he tortures her, Helena arrives and kills Daniel. In the ranch it is revealed that Henrik took Helena's [[egg cell]]s for [[in vitro fertilization]].

|WrittenBy = Tony Elliott

|OriginalAirDate = {{Start date|2014|5|17}}

|Viewers = 0.510<ref>{{Cite web|url=http://www.thefutoncritic.com/ratings/2014/05/20/saturdays-cable-ratings-and-broadcast-finals-48-hours-tops-viewers-dateline-leads-demos-460215/cable_20140517/|title=Saturday's Cable Ratings & Broadcast Finals: "48 Hours" Tops Viewers, "Dateline" Leads Demos|publisher=The Futon Critic|date=May 20, 2014|accessdate=May 20, 2014}}</ref>

|ShortSummary = Rachel has Paul replace Daniel as her monitor and lover, while also withholding a [[stem cell]] treatment for Cosima. Despite this, Leekie plans to treat Cosima anyway. He later confides in Cosima that the original clone genome was lost in a lab fire; the genome would have provided the cure for the illness. Meanwhile, Paul, under Rachel's orders, storms in on Felix and get his fingerprints on Daniel's gun to frame him for the police officer's murder. He gives Sarah until morning to produce Kira. Sarah places Helena in Art's custody to learn more about the Proletheans. Helena escapes, but provides Art and Sarah clues to the location of Maggie Chen's locker. There, the two find clues relating to Ethan Duncan's location, and that Helena intends to assassinate Rachel. Sarah finds Helena and talks her out of killing Rachel, and under Leekie's promise that he will drop the charges against Felix, the two set off to find Ethan.

|WrittenBy = Chris Roberts

|OriginalAirDate = {{Start date|2014|5|24}}

|Viewers = 0.541<ref>{{Cite web|url=http://www.thefutoncritic.com/ratings/2014/05/28/saturdays-cable-ratings-and-broadcast-finals-nba-playoffs-claim-top-spot-for-espn-958213/cable_20140524/|title=Saturday's Cable Ratings & Broadcast Finals: NBA Playoffs Claim Top Spot for ESPN|publisher=The Futon Critic|date=May 28, 2014|accessdate=May 31, 2014}}</ref>

|ShortSummary = Sarah and Helena arrive at a church where Ethan has been. Sarah visits the archives to learn more about Ethan, and with the aid of Art and Felix investigating the files from Maggie's locker, learns that he changed his name to Andrew Peckham. Helena finds a bar and makes a connection with a local man Jesse, but she is later arrested for fighting with some drunks. Mark and Gracie later invite Helena back to Henrik's ranch to allow herself to be inseminated with her own fertilized eggs. Scott Smith, a fellow student of Cosima's, joins her and Delphine at Dyad, and learns that the stem cells Cosima was given belong to Kira. At rehab, Alison befriends Vic, who is later revealed to be an informant for Angela to get dirt on Alison. Sarah arrives at a house to see Mrs. S at the door, her old contacts having protected a scientist years ago. Sarah meets Ethan, who informs Sarah that he started the clone project until it was hijacked by Leekie and the neolutionists in 1977. He also fears Leekie, who was behind Susan's death.

|WrittenBy = Aubrey Nealon

|OriginalAirDate = {{Start date|2014|5|31}}

|Viewers = 0.497<ref>{{Cite web|url=http://www.thefutoncritic.com/ratings/2014/06/03/saturdays-cable-ratings-and-broadcast-finals-nba-playoffs-eclipse-the-competition-893314/cable_20140531/|title=Saturday's Cable Ratings & Broadcast Finals: NBA Playoffs Eclipse the Competition|publisher=The Futon Critic|date=June 3, 2014|accessdate=June 3, 2014}}</ref>

|ShortSummary = Alison reveals to Vic that she let Aynsley die, then learns he is Angela's informant. Vic promises not to tell Angela if he sees Sarah. She sees Vic at rehab, but Felix has drugged him, and he collapses. As Alison and Felix hide Vic, Sarah is mistaken for Alison and is forced to attend "Family Day", ultimately resulting in Donnie finding out about the clones, and that Alison was telling the truth about being probed. Mrs. S and Paul arrange a meeting between Rachel and Ethan. After Ethan tells Rachel of her mother's fate, Rachel fires Leekie, and also implies to him that Dyad will be after him. Cosima is angered at Delphine for using Kira's stem cells from a tooth during the car accident. Kira willingly decides to give Cosima another tooth for analysis. Donnie goes to confront Leekie for lying to him, and accidentally shoots him in the head.

|WrittenBy = Karen Walton

|OriginalAirDate = {{Start date|2014|6|7}}

|Viewers = 0.576<ref>{{Cite web|url=http://www.thefutoncritic.com/ratings/2014/06/10/saturdays-cable-ratings-and-broadcast-finals-nbc-rides-stanley-cup-finals-to-victory-788412/cable_20140607/|title=Saturday's Cable Ratings & Broadcast Finals: NBC Rides Stanley Cup Finals to Victory|publisher=The Futon Critic|date=June 10, 2014|accessdate=June 10, 2014}}</ref>

|ShortSummary = Art receives a call on Beth's old cell phone from Tony, a [[transgender]] clone who promises his dying friend, Sammy, that he will deliver a message to Beth. Tony stays at Felix's apartment until Sarah arrives to tell him that Beth is dead, and reveals his origin. Tony delivers the message; "Tell Beth to keep the faith. Paul's like me. He's on it. He's a ghost." Alison learns Donnie intends to leave, prompting her to admit to being responsible for Aynsley's death. There, Donnie confesses to killing Leekie, and the two begin work to cover up. Sarah and Mrs. S agree to transport Ethan Duncan to the Dyad to start work on a synthetic therapy that may cure Cosima of her illness. Ethan reveals to Rachel that the clones were always intended to be infertile, and views Sarah as a "failure". Before leaving, he hands Kira the book ''[[The Island of Doctor Moreau]]'', which houses all of his secrets in its margins. As Ethan and Cosima begin to work, Cosima collapses and goes into violent convulsions.

|WrittenBy = Alex Levine

|OriginalAirDate = {{Start date|2014|6|14}}

|Viewers = 0.613<ref>{{Cite web|url=http://www.thefutoncritic.com/ratings/2014/06/17/saturdays-cable-ratings-and-broadcast-finals-espn-tops-demos-with-world-cup-soccer-587411/cable_20140614/|title=Saturday's Cable Ratings & Broadcast Finals: ESPN Tops Demos with World Cup Soccer|publisher=The Futon Critic|date=June 17, 2014|accessdate=June 17, 2014}}</ref>

|ShortSummary = Rachel appoints Delphine as Leekie's replacement for director of clone research. Learning that Kira's [[bone marrow]] might save Cosima, Sarah asks Kira, who agrees to donate some. As Alison and Donnie work to bury Leekie in their garage, Vic returns to either blackmail her or discover new dirt for Angela. Suspecting that Angela's operation is not official, a newly assertive Donnie confronts Angela to chase them both away. Burying Leekie causes the couple to have a new-found passion, and they have sex. Helena and Gracie are implanted with Helena's eggs fertilized with Henrik's sperm. Helena comes to learn that Henrik intends to impregnate several other women with Helena's eggs, she helps Gracie and Mark run away while Helena kills Henrik and burns the farm down. Rachel, disillusioned at the prospect of not being able to have children, tricks Delphine into distracting Sarah; while Rachel, posing as Sarah, abducts Kira.

|WrittenBy = Graeme Manson

|OriginalAirDate = {{Start date|2014|6|21}}

|Viewers = 0.538<ref>{{Cite web|url=http://www.thefutoncritic.com/ratings/2014/06/24/saturdays-cable-ratings-and-broadcast-finals-crisis-swan-song-tops-originals-411221/cable_20140621/|title=Saturday's Cable Ratings & Broadcast Finals: "Crisis" Swan Song Tops Originals|publisher=The Futon Critic|date=June 24, 2014|accessdate=June 25, 2014}}</ref>

|ShortSummary = Sarah surrenders to Dyad hoping to secure Kira's safety, but is imprisoned. Rachel deliberately separates Delphine from Cosima by sending her to Germany. Ethan commits suicide to prevent Rachel from getting the code key. Kira steals a cell phone and contacts Cal, who goes to Mrs. S. They meet Paul, who is revealed to be in the military, and Marion Bowles, a Dyad executive. Scott and Cosima devise a plan to break Sarah free by making a make-shift weapon out of a [[fire extinguisher]]. Rachel sabotages Cosima's treatment by destroying the bone marrow, at which point Sarah uses the weapon, shooting a pencil into Rachel's eye. They all escape Dyad with Marion's aid, who invites Sarah to meet her the next day. The next morning, Helena leaves, but is kidnapped by the military, arranged by Paul and Mrs. S. Kira hands Cosima the novel with Ethan's sequences needed to save her life. Sarah visits Marion's home, and meets Charlotte, a clone of Kira's age and the only survivor of the second Leda batch. Marion explains that the military controlled a male clone project, Castor, with the clones looking like Mark.

All titles of the third season are quotes from the [[Eisenhower's farewell address|farewell address]] of [[Dwight Eisenhower]].<ref>{{cite web|last=Nguyen|first=Hanh|title=Here's Everything You Need to Know About Orphan Black's New Season|url=http://www.tvguide.com/news/orphan-black-season-3-premiere-guide/|work=TV Guide|date=April 15, 2015|accessdate=April 18, 2015}}</ref> The premiere episode debuted on all five of [[AMC Networks]]' cable channels–[[BBC America]], [[AMC (TV channel)|AMC]], [[IFC (U.S. TV network)|IFC]], [[SundanceTV]] and [[WE tv]]–and received 1.27 million cumulative viewers across all five airings.<ref name="3.01"/> Likewise, in Canada, the season premiere was simulcast on [[Space (TV channel)|Space]], [[CTV Television Network|CTV]], [[Bravo (Canada)|Bravo]], and [[MTV Canada]].<ref>{{cite web|title=Space Celebrates the Return of its Original Canadian Series ORPHAN BLACK with Multi-Channel Roadblock Season Premiere April 18|url=http://www.bellmedia.ca/pr/press/space-celebrates-return-original-canadian-series-orphan-black-april-18/|publisher=[[Bell Media]]|date=March 11, 2015|accessdate=July 19, 2015}}</ref>

{{Episode list

|EpisodeNumber = 21

|WrittenBy = [[Graeme Manson]]

|OriginalAirDate = {{Start date|2015|4|18}}

|Viewers = 0.535<ref name="3.01">{{cite web |url=http://deadline.com/2015/04/orphan-black-season-3-ratings-tatiana-maslany-bbc-america-amc-networks-1201415409/ |title='Orphan Black' Ratings Hit Debut Low On BBC America, Soar On All AMC Networks |publisher=Deadline.com |first=Dominic |last=Patten |date=April 23, 2015 |accessdate=April 28, 2015}}</ref>

|ShortSummary = While Cosima's condition is improving, Delphine takes over Rachel's duties at Dyad, but the two break up. Delphine shows Sarah a video of two Castor clones, Rudy and Seth, attempting to abduct Krystal Goderitch, a Leda clone; Rudy is the imprisoned clone in Marion's house. After Rudy tells Sarah to "count your sisters", she learns Helena is missing and further resents Mrs. S for taking part in her disappearance. Later Topside official Ferdinand arrives to talk to Rachel. Sarah impersonates her to avoid him knowing of her condition. Sarah learns that Ferdinand took part in "Helsinki", assassinating six self aware Leda clones in Finland, and he is under Rachel's orders to kill those in the Clone Club, starting with Alison. Delphine manages to learn about Ferdinand's purpose through torturing the now brain-damaged Rachel and manages to have him call off the assassinations. Meanwhile, Alison decides to run for school trustee against Marci Coates to oppose Marci's plans on rezoning the school district. Seth breaks Rudy free.

|WrittenBy = Aubrey Nealon

|OriginalAirDate = {{Start date|2015|4|25}}

|Viewers = 0.420<ref>{{cite web |url=http://headlineplanet.com/home/2015/04/28/ratings-bbc-americas-orphan-black-tanks-this-week/ |title=Ratings: BBC America's "Orphan Black" Tanks This Week |publisher=Headline Planet |first=Brian |last=Cantor |date=April 28, 2015 |accessdate=April 28, 2015}}</ref>

|ShortSummary = Sarah learns from Art that Rudy and Seth assaulted a woman in a hotel and took a lock of her hair. Seth is revealed to be suffering from a degenerative disorder. Helena is being held in a controlled military zone and subjected to testing where her captor Doctor Virginia Coady learns of her pregnancy. Rudy and Seth search for the original clone tissue in Felix's apartment. Rudy holds Kira hostage to gather information from Sarah; he does not believe Sarah's claims that Ethan Duncan did not leave original tissue samples with her. When Seth suffers a seizure outside while holding a knife to Cal, Rudy retreats and ends Seth's suffering by killing him. Realizing Kira is not safe with Sarah, she and Cal move to [[Iceland]] while Sarah goes to look for Helena. Meanwhile, Cosima and Scott work with Dr. Nealon to understand Cosima's recovery, despite her and Scott's lack of trust for him. Alison and Donnie hatch a plan to turn the tide for her campaign by buying Ramon's drugs.

|WrittenBy = Chris Roberts

|OriginalAirDate = {{Start date|2015|5|2}}

|Viewers = 0.443<ref>{{cite web |url=http://headlineplanet.com/home/2015/05/05/ratings-bbc-americas-orphan-black-rises-this-week/ |title=Ratings: BBC America's "Orphan Black" Makes Gains This Week |publisher=Headline Planet |first=Brian |last=Cantor |date=May 5, 2015 |accessdate=May 5, 2015}}</ref>

|ShortSummary = Art and Sarah work together to find a lead on Mark's location. Mark reveals to Gracie that he was sent by the military to infiltrate the Proletheans to find the original Castor DNA, which he believes Henrik entrusted to farmer Willard Finch for safe keeping. It is believed the DNA would be used to cure the Castor defect. Gracie recovers the box from Finch, but there is no DNA inside. Henrik's wife Bonnie tracks Gracie down to bring her back to the Proletheans. Sarah learns that Art is devoted to helping the Clone Club because he was in love with Beth. Cosima extracts Seth's brain and learns that like the Leda clones, the Castor clones are also suffering from a defect, albeit a neurological one, as well as determining that both sets of clones are biological siblings. Alison gains support for her campaign after selling the other mothers drugs hidden in bars of soap. Nealon treats Rachel's brain damage. Mark confronts Finch again but he dies from a [[heart attack]] during the torture. Sarah's arrival is soon followed by Bonnie, who shoots Mark.

|WrittenBy = [[Russ Cochrane]]

|OriginalAirDate = {{Start date|2015|5|9}}

|Viewers = 0.406<ref>{{cite web |url=http://headlineplanet.com/home/2015/05/12/ratings-bbc-americas-orphan-black-viewership-hits-season-low/ |title=Ratings: BBC America's "Orphan Black" Viewership Hits Season Low |publisher=Headline Planet |first=Brian |last=Cantor |date=May 12, 2015 |accessdate=May 13, 2015}}</ref>

|ShortSummary = Sarah evades Bonnie and escapes with a wounded Mark. They arrive at an empty house where Sarah treats Mark's wounds. When Mark loses consciousness, Sarah recovers his motel key and finds Henrik's box, where she learns he worked with Ethan, and Henrik used the DNA to produce his own clone, Abel. When Mark finds her, he reveals the baby died shortly after birth, so they go to a grave yard to recover his body. Gracie's pregnancy ends with a miscarriage, and Bonnie, believing it to be punishment from God for marrying Mark, shuns her. Alison finds herself wanted by Ramon's boss, who is revealed to be her ex-boyfriend Jason Kellerman. The two decide to work together to distribute the drugs. Felix sets up a dating profile for Cosima to get over Delphine. Helena manages to escape from her cell and comes across a sick Castor clone, Parsons, that Coady is experimenting on. Helena kills him out of mercy before she is captured again. Sarah recovers Abel's remains, but it is intercepted by Rudy. Sarah attempts to flee, but Mark and Rudy capture her.

|WrittenBy = Alex Levine

|OriginalAirDate = {{Start date|2015|5|16}}

|Viewers = 0.460<ref>{{cite web |url=http://headlineplanet.com/home/2015/05/19/ratings-bbc-americas-orphan-black-adds-viewers-slips-in-demo/ |title=Ratings: BBC America's "Orphan Black" Adds Viewers, Slips in Demo |publisher=Headline Planet |first=Brian |last=Cantor |date=May 19, 2015 |accessdate=May 19, 2015}}</ref>

|ShortSummary = Sarah is taken to the Castor base, much to Paul's dismay; Mark would have let her go, but since deranged Rudy was there, this was the best option. Sarah also has a strained reunion with Helena, who blames her for her capture; Coady had been feeding her lies about the capture, indicating Sarah, not Siobhan was responsible. Although Coady assures Paul no harm would come to Sarah, she still collects a lot of her blood to gather stem cells. Cosima goes on a blind date with Shay Davydov ([[Ksenia Solo]]), a [[Holistic health|holistic]] healer, and quickly begin a physical relationship. However, the date is monitored. Gracie, with nowhere to go, approaches Art, who takes her to Felix and Mrs. S. There, Gracie comes out of her shell and parties with the others, getting drunk before suffering a seizure, displaying bloodshot eyes. Sarah and Helena plot an escape, and Helena successfully exits her cell, but she decides to leave Sarah behind. As she is about to leave the compound, she begins to have second thoughts. Art also meets with the woman assaulted by Rudy and Seth, learning that she has the same symptoms as Gracie.

|WrittenBy = Aubrey Nealon

|OriginalAirDate = {{Start date|2015|5|23}}

|Viewers = 0.393<ref>{{cite web |url=http://headlineplanet.com/home/2015/05/27/ratings-bbc-americas-orphan-black-falls-to-a-season-low/ |title=Ratings: BBC America's "Orphan Black" Falls to a Season Low |publisher=Headline Planet |first=Brian |last=Cantor |date=May 27, 2015 |accessdate=May 27, 2015}}</ref>

|ShortSummary = Paul discovers the hair samples from the women the Castor clones assaulted, and that Sarah is suffering from negative side effects after being given some of Rudy's blood. Alison makes lots of money from the drug deals and plots with Jason to expand further by buying her mother's beauty shop ''Bubbles'' to be used as a front. In an attempt to find Sarah, Felix has Scott bring him to Rachel to learn her location but Rachel does not know. However, Scott realizes that Rachel was painting symbols from Ethan's notes. Cosima examines Gracie and learns that the Castors' defect is sexually transmitted and renders women infertile. Paul has Coady arrested and takes charge of the base until reinforcements arrive. However, he later realizes that even his superior David Benchman is conspiring against him, as Coady is planning to weaponize the defect. Rudy is recalled from searching for Helena to help Coady. Paul helps Sarah, who has recovered, to escape, but he decides to stay behind. He kills a Castor clone, but is stabbed in the process. Paul urges Coady to stop. When she responds by shooting him, a dying Paul releases a grenade, destroying Abel's remains. Helena, who came back, finds Sarah on the way out.

|WrittenBy = [[Sherry White]]

|OriginalAirDate = {{Start date|2015|5|30}}

|Viewers = 0.372<ref>{{cite web |url=http://headlineplanet.com/home/2015/06/02/ratings-orphan-black-viewership-declines-to-another-two-year-low/ |title=Ratings: "Orphan Black" Viewership Declines to Another Two-Year Low |publisher=Headline Planet |first=Brian |last=Cantor |date=June 2, 2015 |accessdate=June 2, 2015}}</ref>

|ShortSummary = After escaping the Castor camp, Sarah and Helena meet Mrs. S. at a local bar, where Helena wants to kill her for selling her out. After heated discussion, Mrs. S promises that Sarah, Kira, Felix, herself and all the other "sisters" will be the family Helena never had. Delphine asks Cosima for a urine sample, but Cosima double crosses her by asking Alison to give hers. Meanwhile, Alison's mother Connie refuses to sell her store. When Donnie and Jason try to pay their supplier Pouchy, Donnie accidentally gives Alison's signatures that support her campaign instead. Pouchy holds Donnie until the money arrives. Alison and Felix attend a campaign event at a local school where Felix arranges for Cosima to pose as Alison for the photography shoot. Alison pays Pouchy, and she has Donnie released. She then takes over from Cosima-as-Alison and gives an impassioned campaign speech, gaining more support over Marci. Connie decides to sign the papers to ''Bubbles''. Alison turns down Cosima's attempt to substitute a urine sample, suspecting her illness has resurfaced when she begins coughing again. Later, Cosima experiences bleeding from her groin during a bath. Scott spends time with Rachel in order to decode Ethan's notes.

|WrittenBy = Graeme Manson & Chris Roberts

|OriginalAirDate = {{Start date|2015|6|6}}

|Viewers = 0.522<ref>{{cite web |url=http://headlineplanet.com/home/2015/06/09/ratings-orphan-black-rebounds-with-most-watched-episode-since-season-premiere/ |title=Ratings: "Orphan Black" rebounds with most watched episode since season premiere |publisher=Headline Planet |first=Brian |last=Cantor |date=June 9, 2015 |accessdate=June 9, 2015}}</ref>

|ShortSummary = Delphine meets the Leda clone Krystal and afterward informs Nealon that she has no idea about clones. David Benchman informs Coady that they have infiltrated Dyad. Rachel will only decode the symbols in Ethan's ''The Island of Doctor Moreau'' book if Sarah and Scott help her escape to [[Taiwan]] with a new life using Krystal's identity. Sarah and Felix go to Krystal's place of work, a [[beauty salon]], where Felix poses as a customer to steal her wallet. Felix discovers that although Krystal is not a self-aware clone, she began investigating her attempted kidnapping by Rudy and Seth. Rudy shows up at Scott's apartment and steals Ethan's book by threatening Scott's cat. Delphine suspects that Rachel or Shay have been spying for Castor people. Delphine fires Scott for not reporting the book earlier; Scott previously made a copy of the book. Cosima refuses to accept more treatment using Kyra's stem cells, and she resigns from Dyad. Rachel begins translating but Nealon busts in, taking her and the book before smuggling Rachel away for prosthetic eye surgery using Krystal's identity. The neolutionists have held the real Krystal in a medically-induced coma in Rachel's place at Dyad. From what they saw translated, Mrs. S, Felix, and Sarah believe the Castor original is in London.

|WrittenBy = Russ Cochrane

|OriginalAirDate = {{Start date|2015|6|13}}

|Viewers = 0.401<ref>{{cite web |url=http://headlineplanet.com/home/2015/06/16/ratings-orphan-black-sinks-this-week-avoids-viewership-low/ |title=Ratings: "Orphan Black" Sinks This Week, Nearly Loses All of Last Week's Gains |publisher=Headline Planet |first=Brian |last=Cantor |date=June 16, 2015 |accessdate=June 16, 2015}}</ref>

|ShortSummary = Felix, Sarah and Mrs. S arrive in London to meet with Terrance who believes Ethan's coded numbers relate to a prisoner identity. As Terrance investigates, Ferdinand has him beaten to death. Cosima comes to believe that Shay is a spy working for Castor. When Delphine interrogates Shay, she intends to stage her death as a suicide. However, Cosima calls her off because Gracie admits that she betrayed them to help Mark. Pouchy demands that Donnie return the drugs, keeping the canister with Helena's eggs as collateral. Donnie and Helena return the drugs, but Helena kills Pouchy and his crew after they threaten Alison's children, and takes all of the money. Mrs. S previously stated that to stop all the danger, the only way is to kill the original source, but when the dying Terrance whispers what he found out, Mrs. S insists that she, Sarah and Felix return home and stop investigating. Sarah takes Terrance's phone, leading to the address of Kendall Mallone, Siobhan's mother. Kendall reveals that she submitted to Ethan's medical tests while in prison, and she is the original to both Leda and Castor as she is a [[Chimera (genetics)|Chimera]] carrying two genetic lines; Kendall absorbed a male twin in her mother's womb.

|WrittenBy = Graeme Manson

|OriginalAirDate = {{Start date|2015|6|20}}

|Viewers = 0.428<ref>{{cite web |url=http://headlineplanet.com/home/2015/06/23/ratings-orphan-black-rises-for-season-3-finale/ |title=Ratings: "Orphan Black" Rises for Season 3 Finale |publisher=Headline Planet |first=Brian |last=Cantor |date=June 23, 2015 |accessdate=June 23, 2015}}</ref>

|ShortSummary = Kendall returns with the others to Canada, with Art's assistance. Cosima later obtains biological material from Kendall. Doctor Coady has Rudy follow Alison, who lures Rudy to his garage, where Helena waits to kill him. Delphine and Sarah make a deal with Ferdinand to stop Coady. Sarah and Felix find Gracie and Mark; Mark assists them by posing as Rudy and giving Coady a location for Kendall, where Ferdinand captures Coady. Kendall reveals that she arranged for Sarah to arrive in S's care. Delphine realizes that Krystal has taken Rachel's place in Dyad's ward, and has Nealon arrested. Nealon reveals that the neolutionists run both Leda and Castor, and that Rachel is in their custody. Delphine is forced to kill Nealon when he attacks her and tries to place a worm into her mouth. Upon learning of Nealon's neolutionist agenda, Ferdinand, who despises neolutionists, defects. The Clone Club and their families, along with Art and Scott, gather at ''Bubbles'' to celebrate their victory and Alison's election win, and to remember Beth. Delphine reconciles with Cosima, before being shot by an unseen figure. Rachel, with a new prosthetic eye, is being held in a house where she reunites with Charlotte and another woman. In Iceland, Kendall goes into hiding and Sarah reunites with Kira.

===Season 4 (2016)===

All season 4 titles are quotes from the works of [[Donna Haraway]].<ref>{{cite web |url=http://blogs.wsj.com/speakeasy/2016/04/15/orphan-black-season-4-premiere-recap-the-collapse-of-nature/ |title=‘Orphan Black’ Season 4 Premiere Recap: ‘The Collapse of Nature’ |work=The Wall Street Journal |first=Jennifer |last=Hodson |date=April 15, 2016 |accessdate=April 16, 2016}}</ref>

{{Episode list

|EpisodeNumber = 31

|WrittenBy = [[Graeme Manson]]

|OriginalAirDate = {{Start date|2016|4|14}}

|Viewers = 0.229<ref>{{cite web |url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-4-14-2016.html |title=UPDATED: SHOWBUZZDAILY's Top 150 Thursday Cable Originals & Network Finals: 4.14.2016 |publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=April 15, 2016 |accessdate=April 15, 2016}}</ref>

|ShortSummary = M.K., wearing a sheep mask, witnesses two paramedics burying a man in the forest. She phones Beth Childs, who visits the scene the next day with Art, discovering the dead man's cheek chopped out. M.K. tells Beth that the dead man is linked to neolution. Beth visits Club Neolution, where body-mod Trina informs her of the self-directed nature of Neolution. Olivier reports Beth's visit to Aldous Leekie, and they consider whether Paul has lost control of Beth. Beth visits Leekie hoping to gain more information where Evie Cho recognizes Beth as a Leda clone. Beth installs borrowed surveillance equipment in her apartment. Trina contacts Beth concerned for her boyfriend. Beth finds the paramedics killing Trina's boyfriend, under Detective Duko's supervision and the guise of operating on his cheek. Beth inadvertently attracts their attention, and mistakenly shoots a bystander—later revealed to be Prolethian Maggie Chen. Beth calls Art, who helps cover for her. Detective Duko is positioned to help Beth through the investigation, unaware that Beth knows his real role. In the present, Sarah's Icelandic retreat is interrupted by a phone call from Art and M.K., who warn Sarah to flee as Neolution has found them.

|WrittenBy = [[Russ Cochrane]]

|OriginalAirDate = {{Start date|2016|4|21}}

|Viewers = 0.271<ref>{{cite web |url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-4-21-2016.html |title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 4.21.2016 |publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=April 22, 2016 |accessdate=April 22, 2016}}</ref>

|ShortSummary = Following M.K.'s warning and the sight of incoming vehicles, Sarah, Kira, Mrs. S, and Kendall flee Iceland and return home. Helena learns that she is having identical twins which causes Alison to yearn for her own children. Cosima is upset about Delphine's disappearance. Sarah decides that to learn about Neolution they must make contact with the reclusive M.K. Knowing that Beth was in contact with M.K., Sarah and Art begin to investigate Beth's final days. They discover that Beth was spying on Paul with surveillance equipment borrowed from Raj, with the tapes also revealing Beth was contacted by Trina. Sarah and Felix go to the Neolution club, where the two argue when Felix reveals he has been searching for his birth family. They split and Sarah encounters Dizzy who mistakes Sarah for M.K. and shows her a video of an operation on a Neolution follower which kills him when the bot implanted in his cheek is ruptured. She quickly leaves and tries to meet M.K. who, via phone, reveals she is feared 'it' would kill Sarah like it killed Beth, before fleeing the scene when Sarah spots her. In flashbacks, on the night Beth kills herself, she tells M.K. to "watch the others". Sarah is attacked by Neolution paramedics believing her to be M.K. When they discover it is actually Sarah, they retreat. Sarah runs home and discovers she already has a bot implanted in her cheek. Kendall reveals to Scott that she has leukemia but has not told the others.

|WrittenBy = Aubrey Nealon

|OriginalAirDate = {{Start date|2016|4|28}}

|Viewers = 0.242<ref>{{cite web|url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-4-28-2016.html|title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 4.28.2016 |publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=April 29, 2016 |accessdate=April 29, 2016}}</ref>

|ShortSummary = Ira, a Castor clone raised outside of the military by Susan Duncan, examines Rachel’s new eye. Susan, Charlotte’s new guardian, returns to the Island after unsuccessfully attempting to track down Kendall. Kira senses things and she is not happy with people keeping the truth from her. Cosima examines Sarah’s bot but they are unsure of its purpose. Alison and Donnie begin to dig up Dr. Leekie’s body in the hope that he possesses an implanted bot (as most high level Neolutionists do) for Cosima to study. As they begin to excavate, the police arrive to investigate the murder of Pouchy’s drug ring, who were in possession of Vote Alison Hendrix campaign material, forcing Helena to play Alison during the detectives' interrogation. Sarah meets Felix’s biological sister Adele and immediately doubts her intentions, causing Sarah and Felix to split on bad terms. Alison and Donnie inform Cosima that they killed Leekie and have his bot for her to examine. Art sees on Beth's surveillance video that Detective Duko visited her. Art finds information on the man whose bot exploded (on the video that Sarah saw at the club last episode). With Art’s intel, Sarah visits a dental clinic where one of the employees recognizes her as Beth, who previously investigated there. She promises to remove the bot but seemingly pierces it instead, telling Sarah not to move as the toxins will kill her, and claiming that she has contacted her superiors, calling her lucky to be implanted with the technology. Ferdinand arrives instead, killing the dentist and freeing Sarah as she would already be dead had the bot actually been pierced. Rachel learns for the first time that Charlotte was cloned from herself. Rachel gets word to Ferdinand that Susan is alive. Susan, after telling Rachel that she does not love her, apologizes for her detachment and informs her that their purpose is for the greater good; to control human evolution and create a more perfect human being.

|WrittenBy = Alex Levine

|OriginalAirDate = {{Start date|2016|5|5}}

|Viewers = 0.218<ref>{{cite web|url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-5-5-2016.html|title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 5.5.2016 |publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=May 6, 2016 |accessdate=May 6, 2016}}</ref>

|ShortSummary = Ferdinand, having saved Sarah, convinces them to decrypt files that Rachel sent him, as the files could lead to Susan Duncan who can probably deal with Sarah's bot. After Leekie's head containing the bot is delivered to Cosima, she and Scott begin investigating its true purpose. Trina, mistaking Alison for Beth, confronts Alison in a diner for investigating Lifespring Fertility Clinic, having been a carrier and trusting Beth in confidence. Posing as a gay couple, Felix and Donnie visit the clinic looking for information on Brightborn conception technologies. With Alison becoming more emotional about her (in)fertility issues, Helena buries her expired nitrogen eggs and leaves the Hendrixes behind. Sarah goes to M.K. for help decrypting Rachel's files. Realizing that Rachel and Sarah are collaborating with Ferdinand, M.K. lures him to Beth's house and tricks him into sitting on a pressure bomb. M.K. confronts him on the Helsinki event, which wiped out multiple clones and their friends and family, including M.K.'s best friend Niki, another Leda clone. The letters "M.K." were from clone number 3MK29A whose name was Veera Suominen, a clone that escaped the purge and now plans to avenge those responsible for the deaths. Sarah turns up to stop M.K./Veera, needing Ferdinand alive to help remove the bot in her cheek, which Cosima has discovered is performing gene editing to change her DNA. M.K. leaves with Ferdinand's money. Mrs. S defuses the bomb and Sarah declares that her score with Ferdinand is even. Elsewhere, knowing Charlotte is sick, Rachel makes the case that Charlotte should be left to die, refusing to intervene with her illness as the data would be invaluable. Susan agrees but reveals that she knows of Rachel's contact with Ferdinand. Cosima and Scott watch the Brightborn Fertility information video, presented by Evie Cho.

|WrittenBy = Kate Melville

|OriginalAirDate = {{Start date|2016|5|12}}

|Viewers = 0.223<ref>{{cite web|url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-5-12-2016.html|title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 5.12.2016 |publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=May 13, 2016 |accessdate=May 13, 2016}}</ref>

|ShortSummary = Sarah discovers that Brightborn owns GeneConnexion, the company that united Felix and Adele, so she sends their DNA to Scott to verify the familial match. Cosima goes undercover at Brightborn with Donnie, posing as a surrogate mother. Evie Cho is present, and the two fear that the high-level Neo would recognize a clone. At the same time, Krystal Goderitch continues investigating and poses as a prospective parent. Evie spots Krysal and informs Susan (who is visiting with Ira), but they mistake her for Sarah. While Cosima searches for Brightborn's lab, Donnie is shocked when he sees Krystal. Elsewhere in the building, Susan meets Cosima who is unaware of Susan's identity, and discuss Brightborn’s policies and techniques. Cosima steals her swipe card that gives access to secure areas. Later, Adele turns up to a family meal and after arguing with Felix, Sarah discovers that the two are indeed related and apologizes. Detective Duko warns Art to drop his interest in Beth. Alison confesses to Sarah that Helena took off. Donnie presents himself to Krystal as a Brightborn spa employee, and she shares her misguided suspicion that Dyad and Brightborn are putting stem cells in cosmetics. Roxie and Frank lock Krystal in a room, thinking her to be Cosima. Susan directs Krystal's release because she is harmless, then Krystal spots Ira in the building and begins to scream. Cosima comes across a pregnancy where the baby is delivered with severe deformities. When Susan walks in, Cosima realizes who she is and the two dispute the moralities of experimenting on human lives. Susan offers Cosima the opportunity to collaborate with them and to create a cure using the original’s genome. Kira tells Sarah that she feels each of the Leda sisters.

|WrittenBy = Chris Roberts

|OriginalAirDate = {{Start date|2016|5|19}}

|Viewers = 0.248<ref>{{cite web|url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-5-19-2016.html|title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 5.19.2016|publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=May 20, 2016 |accessdate=May 20, 2016}}</ref>

|ShortSummary = In a flashback, Beth wearing a blonde wig enters a private Brightborn event with Susan and Evie in attendance. When Susan leaves the room, Beth follows and holds a gun to her head, threatening to kill her. Susan argues that as the leader of Neolution, she is also protecting them and that she genuinely loves the clones. Beth leaves without shooting. In the present, Krystal turns up at the police station seeking protection from the guys who look like Castors. Art spots Krystal and arranges for her to meet Felix. Krystal reveals that she saw Delphine get shot. Evie confirms that Sarah’s bot is attempting to isolate the gene making them sick by activating specific genes in Sarah. Running out of time, Sarah and Cosima take up Susan’s offer to share Kendall’s genome, without consulting Mrs. S. Refusing to share the Castor pathogen by sharing Kendall’s genome, Cosima suggests isolating the Leda cell line, using Kendall’s cancer cells which have multiplied from a single Leda gene and thus have not impacted the Castor gene line. After Evie and Cosima remove Sarah’s bot, she returns home to find Kendall’s cigarettes in a pool of blood and that Kendall cannot be contacted. Sarah destroys the samples and they take Susan hostage, believing she orchestrated Kendall's abduction; in turn, Cosima is taken hostage at Brightborn. Sarah believes Ira is behind the attack after denying him a cure but he is found unconscious after attempting suicide by drug overdose. Brightborn wipes Scott and Cosima’s research and they realize that Evie is behind the attack, wanting Leda destroyed. Duko prepares to burn Kendall to death and destroy Leda’s hope of a cure, as instructed by Evie. Evie grants Cosima permission to say goodbye before Kendall is murdered. Evie tells Cosima that Delphine was shot dead, before instructing her to tell Susan that the original is dead and to tell Sarah that it is over or Beth died for nothing. A flashback reveals that Evie misled Beth to kill Susan and, Beth having not followed through, Evie threatens Beth by saying that she knows too much and should use the gun on herself to save her sisters. Beth, after physically attacking Evie, is shown walking to the train platform after saying goodbye to M.K.

|WrittenBy = Nikolijne Troubetzkoy and Graeme Manson

|OriginalAirDate = {{Start date|2016|5|26}}

|Viewers = 0.258<ref>{{cite web|url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-5-26-2016.html|title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 5.26.2016|publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=May 27, 2016 |accessdate=May 27, 2016}}</ref>

|ShortSummary = With their hope of a cure gone, Sarah and Cosima both attempt to come to terms with their input in the deal that led to Kendall’s death. Alison pushes forward with Gemma’s birthday party to maintain a sense of normalcy. Susan returns to the Island and informs Rachel of the creator of Neolutionism, Dr. P.T. Westmoreland, noting that he built the facilities they live in over a century ago. Mrs. S disowns Sarah who begins to spin off the rails, drinking, partying and taking drugs. Sarah’s story starts to parallel Beth’s and she begins to hallucinate her. Art confirms that it was Detective Duko who killed Kendall and proceeds to attack him. Duko tells him that Neolution are after Art next. Evie has pending approval for her gene therapy technology and plans to dissemble Leda for their assets, cutting loose naive clones and terminating the self-aware clones while refusing to allow Rachel to take a position of importance within Neolution. Police interrupt the Hendrix slumber party and arrest Donnie on suspicion of narcotics trafficking. Duko then shows up and ominously says that he and Alison will be staying in touch. Sarah finds herself at the train station where Beth killed herself, conversing with her one last time. Cosima decides to experiment on herself by inserting Sarah’s bot (which she stole from Brightborn) in her own cheek, as it could cure her or her death could help the Leda clones learn about the disease. Felix talks Cosima out of it, informing her that Krystal saw Delphine get carried away alive after being shot. Felix then arrives at the train station, where Sarah contemplates jumping. He and Beth's apparition talks Sarah out of it and she steps down and returns to Mrs. S's home. M.K. hacks Kira’s computer. Kira calls her the girl in the shadows. Rachel sees a swan in her prosthetic eye.

|WrittenBy = Peter Mohan

|OriginalAirDate = {{Start date|2016|6|2}}

|Viewers = 0.245<ref>{{cite web|url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-6-2-2016.html|title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 6.2.2016|publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=June 3, 2016 |accessdate=June 3, 2016}}</ref>

|ShortSummary = Jailed for drug trafficking, Donnie meets a Neolution plant who threatens him. Alison visits him in jail, with Felix and Adele (a lawyer), who is surprised to see Sarah's ‘twin sister’. Donnie reveals the Neolution threat and believes he won’t survive his prison sentence. M.K. contacts Sarah and meets Cosima, revealing that she has traced Susan and Rachel’s location, revealing Evie’s plan to dissemble Leda and her threat to wipe out the sisters. M.K. helps Sarah and Cosima to contact Susan on the Island to scientifically team up. Susan agrees, but Cosima forces Rachel and Ira out, refusing to trust them. After sending Sarah more information on Duko, M.K. begins coughing up blood due to the same disease killing the Leda clones. Mrs. S, furious over the death of her mother, takes out her sniper rifle to kill Duko. However, Alison arrives to confront him. Duko gives Alison an ultimatum: turn over Sarah’s location or allow Donnie to die; Alison and Donnie are simply caught in the crossfire and the Neolutionists only want Sarah. After being given the day to think about it, a fraught Alison is visited by Felix. Alison seemingly makes the deal, giving Duko Sarah’s location when Donnie is threatened with death. Duko walks into a trap and after he calls off the attack on Donnie, and reveals Evie’s plan to implant bots into millions under the guise of gene therapy, Mrs. S shoots him dead. Cosima comes up with a possible cure: fertilizing Leda eggs with Castor sperm from Ira to create an embryonic stem cell. Sarah hesitantly agrees, and with Sarah’s eggs Cosima flies to the Island where Susan waits to work with her. Rachel’s swan visions become more vivid and a man appears too. Rachel wants to get back to work and restore Susan’s place at the head of Neolution.

|WrittenBy = Alex Levine

|OriginalAirDate = {{Start date|2016|6|9}}

|Viewers = 0.291<ref>{{cite web|url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-6-9-2016.html|title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 6.9.2016|publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=June 10, 2016 |accessdate=June 10, 2016}}</ref>

|ShortSummary = Cosima and Susan collaborate on the Island. In the city, Sarah and Rachel begrudgingly team up to bring down Evie; Rachel suggests that they find two carriers, Tabitha and Kendra, who fled BrightBorn with video evidence of deformed newborn being euthanized. Tabitha is found dead in a pregnancy shelter, supposedly having committed suicide. Sarah sees Trina leave the shelter, and still believing her to be Beth, Trina tells Sarah that Tabitha’s death was not a suicide. Trina asks Sarah to find Kendra in Tisdale, and an investigator overhears and tells Evie. We see where Helena has been living, and a phone call between her and Sarah. Donnie is released from prison and Adele begins to become suspicious about the family, furthered when Helena returns from hibernation and arrives at Felix’s apartment. After a standoff, Adele agrees not to ask questions and leaves on good terms with Felix. Sarah and Art track down Kendra and eventually convince her to go with them, just as Neolution arrive. Art holds them off while Kendra receives a call from Rachel threatening to give one of Kendra's children (currently staying with relatives) to Neolution if she does not go with Ira, who shows up to drive Kendra to the city. Evie Cho is preparing for a press conference regarding the government approval of her bot technology, which uses germline editing to alter DNA. Sarah confronts Ira who reveals that Rachel is with Evie. Rachel, claiming to want to make a deal with Evie and become head of Neolution in exchange for the video evidence, records Evie admitting that Brightborn’s euthanizes deformed newborns. During the press conference the new recording is pushed to every reporter's phone, causing them to mob Evie as Rachel looks on. Neolution paramedic Frank captures Alison and Donnie for information on Duko’s disappearance. Frank ties them up and attempts to insert a fatal bot in Alison’s cheek but Helena bursts in and kills Frank. Rachel’s hallucinations intensify and she sees a tribe-like village, a young brunette girl, the killing of a swan, and a bearded man staring at her. Delphine is shown to be alive.

|WrittenBy = Graeme Manson

|OriginalAirDate = {{Start date|2016|6|16}}

|Viewers = 0.325<ref>{{cite web|url=http://www.showbuzzdaily.com/articles/showbuzzdailys-top-150-thursday-cable-originals-network-finals-6-16-2016.html|title=UPDATED: SHOWBUZZDAILY’s Top 150 Thursday Cable Originals & Network Finals: 6.16.2016|publisher=Showbuzz Daily |first=Mitch |last=Metcalf |date=June 17, 2016 |accessdate=June 17, 2016}}</ref>

|ShortSummary = We see what happened to Delphine. Helena keeps Donnie and Alison safe. After Cosima finds a cure for the Leda clones, Susan cuts off her network access and later locks her in a room. Susan tells Rachel that they can continue the cloning program. Krystal sees Dr. Van Lier's (doctor and mentor to Evie) familiar face on a news clip about Brightborn, and offers information on Delphine's shooting in exchange for information and insight into the investigation. Krystal meets one of her clones for the first time, but doubts their resemblance. Sarah publicly poses as Krystal to get information from Van Lier on the Island's location and Rachel's plan, which involves taking control of Neolution, merging now-gone-Evie's bots with cloning technology. Rachel does not want her mother Susan back on top. Rachel casts aside Ira, then Sarah convinces him to help prevent Rachel from harming Susan. Sarah flies to the Island to save Cosima, whom Charlotte has released saying that Susan wants them to escape by boat before angry Rachel finds them. Susan tells Rachel that in contrast to her sisters, Rachel's existence is a regret. Sarah arrives to find the bleeding Susan, who says Rachel took the stem cells and the Leda cure. Rachel attacks Sarah. Susan tells Rachel who created the prosthetic eye that has given her visions. The man from Rachel's visions leads Cosima and Charlotte to Delphine at a camp on the Island. As Cosima takes a turn for the worse, she tells Delphine that she "finished (our) homework", ie. the cure. Sarah lies bleeding on the beach and learns that Kira and Mrs. S are being held captive by Ferdinand, who has defected to Neolution under Rachel's authority. In the final moments, Rachel gleefully prepares to meet P.T. Westmoreland who founded Neolutionism centuries ago, still alive today.

===Season 5 (2017)===

All season 5 titles are quotes from the poem "1695" by [[Ella Wheeler Wilcox]].<ref name="season5">{{cite web |url=http://www.indiewire.com/2017/05/orphan-black-season-5-trailer-krystal-kira-bbc-america-1201813872/ |title=‘Orphan Black’ Extended Trailer: Could One of the Clone Club Die This Final Season? — Watch |publisher=IndieWire |first=Hanh |last=Nguyen |date=May 8, 2017 |accessdate=May 9, 2017}}</ref>

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|OriginalAirDate = {{Start date|2017|6|10}}

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|OriginalAirDate = {{Start date|2017|6|17}}

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|OriginalAirDate = {{Start date|2017|6|24}}

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