"A Man of Action" is the second episode of the seventh series British comedy series Dad's Army. It was originally transmitted on Friday 22 November 1974.

A parachute mine has ripped up 100 yards of railway track and the gas and water supplies have been cut, the telephone wires are down, and Pike has got his head stuck through the bars of a gate. Mainwaring declares martial law.

Jones and Pike are out on patrol and whilst recreating a childhood prank, Pike gets his head stuck in the park gates. Mainwaring is in the church hall, conducting an interview and photo session with Mr Cheeseman, a member of the local press who is temporarily joining the platoon to report on its activities. Alerted by Jones, Mainwaring and the others come to rescue Pike – unable to free him, they lift the gates off their hinges and carry them back to the church hall with Pike still trapped within them. Once there, Mainwaring tells Cheeseman to keep it secret to avoid public embarrassment.

After securing Pike's gate to the ceiling with rope, they discover an emergency meeting in the office by the town elders (namely the Vicar, Warden Hodges, Inspector Baker and Fire Officer Dale) and learn that Walmington-on-Sea is in the grip of a crisis. The railway line has been heavily bombed, leaving the water, telephone and other vital services damaged. The town is, in effect, totally cut off. The town clerk arrives, panicking, and he and the rest of the committee start bickering about what to do. Realising that they are not providing effective leadership, Mainwaring orders his men to fix bayonets and steps in, effectively performing a coup d'etat and putting the town under martial law. Hodges implores Inspector Baker to arrest him, but Mainwaring points out that they are up against sixteen fully armed men.

He begins issuing a number of stringent edicts to Wilson, Jones and Frazer to shout from their bicycles, including: all looters being shot, all rumour-mongers, defeatists and those not following military law being imprisoned, and for no baths to be taken or liquor to be sold without a permit, which Frazer supports (only because Mainwaring has given him responsibility for alcohol permits). Then, gathering his men behind him, Mainwaring marches on the town hall to take control of the town, denying accusations that he is behaving like "the dictator of some South American Banana republic". Pike is still stuck in the gate, and the town clerk wrongly assumes this is some form of harsh punishment by Mainwaring.

Jones has been given responsibility for bath permits, and old Mr. Bluett comes in, enquiring about how the system works. Despite the confident manner he had departed in, Mainwaring returns from his attempt to seize the town hall, indignantly explaining it was shut by the town clerk, and assuring that he will "deal with him in the morning". Frazer and Wilson say that he is behaving like a tyrant, and usurping the power of the land, but Mainwaring again denies it and says that for their own safety, everyone must "knuckle down" and get used to it.

However, when Captain Swan, a tough officer from GHQ arrives to take over command from him, implementing many of the same policies as he had, Mainwaring is himself outraged and the episode ends with him being locked out of his own office, thanks to Frazer telling Swan where the office is. Wilson laughs at Mainwaring's hypocritical nature.

1. This is the first episode that introduces Mr Cheeseman as a member of the platoon. He had previously appeared in the episode "My British Buddy" as a reporter from the Eastbourne Gazette who photographed Mainwaring being punched by an American Colonel. In the radio adaptation he is replaced by Jonathan Cecil playing a character named Mr Norris.