Los Angeles police officer Larry is shot dead while taking a selfie for his mistress, Amanda. His partner Martin Jones hides the picture from the police and instead shows it to gang leader Damian, who identifies the killer as Jesus Rojas, whose mother Martin killed. In exchange for their silence, they pressure Martin into killing a man for them.

Martin has dinner with the rich father of his 17-year-old girlfriend, Janey, who seems to approve of the relationship. In private, though, he acts bizarrely with Martin, imitating a tiger and making sexual advances toward him.

After more coercion from Damian, Martin decides to do what he's asked. He tracks his target down to a car shop. After a fight with the man, who is naked, Martin kills him.

At Larry's memorial service, where police serve orange juice and pancakes, Martin is promoted to the homicide division.

Damian's gang captures Amanda, claiming she tried to sell Martin out to the Mexicans. They offer him a gun and the opportunity to deal with her as he wants. We are not shown what he does, aside from accepting the gun. Outside, he messages Janey.

Jesus escapes to Mexico to wait it out while things calm down in Los Angeles. His uncle, the terminally ill Don Ricardo, highly revered Rojas's mother, who he sees in her son. He also sees her in his nurse, Yaritza, whom he says he found out in the desert. A mysterious vigilante is killing cartel members, making matters tense with the police. Don Ricardo is also worried about whether his son, Miguel, is suited to take over.

When Don Ricardo dies, Miguel beats up Jesus out of jealousy. He later severely abuses a prostitute before making Yaritza drive her off to be sold. At the exchange, Yaritza instead kills everyone and frees the girl, revealing herself as the vigilante. Jesus and Miguel later make peace, with Jesus helping him to execute several policemen. When he is about to kill the local chief, the scene cuts out, similarly to with Martin and Amanda.

Diana DeYoung is a victim's advocate who moonlights as a healer and appears to have magical powers. She has Viggo Larsen, a one-eyed former FBI agent who is terminally ill, murder pedophiles she learns about through her work. One of the murders goes wrong, and the body is found in a car in a parking lot. Martin, who has just started working homicide, is put on the case. He seems at unease with his middle-aged colleagues, who pull practical jokes on each other and openly celebrate fascism. When Martin finally tracks down Larsen, he does not arrest him. Instead he invites him to a diner, where they find they have a lot in common.

Martin and Larsen begin working together to murder pedophiles for Diana. After one successful job, Larsen monologues about how humans used to have to be animals to survive. As civilization evolved, the animal side stayed beside us. He thinks society is about to collapse due to global warming and rising fascism. The instinctual violent side of humans will come back. He believes it's up to them to protect the innocence in humanity as much as they can.

Influenced by his mentor, Martin begins to question the killings he is doing for Damian's gang. He is asked to kill a Korean man, and unsuccessfully tries to learn why from his employers. From the man himself, Martin learns he owes them $8,000. After he manages to get Martin the money, Damian agrees to let him live. Martin requests that he only be given the worst possible people to kill. Damian suggests two infamous porn directors.

Martin stalks the pornographers. Eventually they stop to drink at a bar, where he casually gets to know them. They suggest he make a movie with him in it. As they are about to take off his clothes, Martin shoots everyone in the room dead. He goes through the studio looking for the rest before giving up and getting in his car. The two remaining pornographers get into an electric car to chase him, but have trouble keeping up. As dawn breaks, the car runs out of power. Martin backs up into them and kills one of them. As he is about to shoot the other, he mentions a girl who's going to die out in the desert, mistakenly believing Martin is after her.

The director takes Martin to the desert, where they dig up a chest containing a chained girl. The director frees her, warning her about Martin in Spanish. He draws a knife and lunges at Martin, who shoots him dead. As Martin helps the girl out of the chest, she grabs the knife and stabs him in the side before running off.

Yaritza and Jesus marry and decide to return to Los Angeles. In preparation, they arrange to have Damian killed, but the wrong man is hit. Jesus humiliates his subordinate for the failure. Later, Yaritza goes to a party arranged by one of Jesus's friends from before Mexico. She ends up playing a guessing game with Janey, which Janey loses when she incorrectly guesses that Yaritza is lying about killing 23 people. For winning, Yaritza is allowed to slap Janey, which she does more than once, even pushing her to the floor and putting her foot on her. Back home, Yaritza tells Jesus that she is his mother reincarnated. Jesus seems to accept this, and calls her his mother as he moves to perform oral sex on her.

Martin has taken sick leave after being stabbed. He spends his free time celebrating Janey's 18th birthday and killing more pedophiles with Larsen. Theo, Janey's father, makes more sexual advances toward Martin when they are alone. He ends up inviting Martin to see a movie, which appears similar to the show itself. Afterwards, Theo starts masturbating while talking about Janey, causing Martin to kill him. Larsen helps Martin get rid of the body. Martin then throws up and confesses who Theo was to Larsen, and admits that he isn't sure why he killed him. He says he doesn't want to be a police officer anymore.

Larsen and Martin visit Damian's gang to cut ties with them, only to find everyone dead and Damian's severed hands. Somewhere else, Jesus describes to a captive Damian all the ways he is going to torture him. Damian suggests that Jesus instead kill him quickly in exchange for telling him who actually killed his mother. Surprised, Jesus agrees, and Damian tells him about Martin. Yaritza kills Damian as he laughs hysterically.

The police perform a bizarre nationalistic play about Jesus to Martin as goodbye. Meanwhile, Janey reports her father missing, and admits to the police that she's been in a relationship with Martin since she was 16. Martin kills another pedophile with Larsen, who is getting too sick to continue the work. When Martin helps him to bed, Larsen asks him to hold him. They embrace for a long time.

Janey and Martin go to the beach, when Jesus' men arrive, killing Janey and capturing Martin. Yaritza continues to secretly kill cartel members. She asks the women she frees to spread word of "the High Priestess of Death." Yaritza and Jesus engage in sadomasochistic sex, with Yaritza playing the dominant role. After torturing Martin for three days, Jesus decapitates him.

After Martin's death, Diana has a vision, with her eyes clouding over. She performs a ritual with lemon-flavored soda, which reveals Yaritza to her and clears her eyes. Meanwhile, Yaritza and Jesus role-play scenes from his childhood, acting out an incestuous relationship between him and his mother. At a meeting with his subordinates, Jesus orders his men to be as brutal and violent as possible, saying he wants to turn the city into "a theme park of pain."

Larsen's mother eats his artificial eye while he is sleeping. Later he finds her dead with his eye by her side. He puts it back into his socket. Larsen later tells Diana that he needs to take his anger out somewhere. She tells him about a camp of pedophiles, but worries he won't come back if she sends him. While she is waiting for him at a diner, Diana tells her waiter about an older version of the story of Little Red Riding Hood. In this version, the wolf rapes Red Riding Hood instead of eating her, and the next day Red Riding Hood comes back armed and kills the wolf. Larsen returns safely, and the two eat apple pie together.

Diana masturbates while using VR equipment, shaves her legs, calls in sick to work, and dances. She prophesies that civilization will soon end and evil will prosper until things reach a breaking point, after which she will declare "the dawn of innocence."

Yaritza visits a bar, where she drinks with a gangster. She asks the girls to play the song about the High Priestess of Death that's been going around. When asked why she requested the song, Yaritza replies by killing all the men in the bar except one. As he begs for mercy, she declares that she will rid the world of evil and kills him.