After escaping from prison, IRA gunman Johnny McQueen spends six months hiding out in a house in the back streets of Belfast. He decides to lead a raid on a mill to get funds for 'The Organisation'. His friends Dennis and Kathleen try to dissuade him, claiming that he is not physically well enough for the job and that his heart just isn't in it any more. Johnny insists on leading the robbery, although he admits that he wishes that the IRA's objectives could be met without resorting to violence.

Although clearly unwell, Johnny meets up with Pat, Nolan and Murphy and they drive over to the mill. The robbery goes according to plan but during the getaway Johnny has a dizzy spell and is stopped by an armed man. During the scuffle Johnny is shot and the man is killed. Johnny gets himself halfway into the getaway car, but Pat drives too fast and eventually Johnny falls out. Pat and Nolan argue about going back to pick him up, but eventually drive away.

Johnny hides in a bomb shelter, while the others head back to the house. Dennis decides to go and look for him and tells Kathleen, who is in love with Johnny, to stay home with Granny. As the police are out in force, rather than risk going straight to the HQ, Pat and Nolan decide to spend some time at Theresa's house. After learning what has happened, she calls the police and arranges for them to be arrested in the street. When they leave her house, the two men are killed in an exchange of gunfire with the police.

Dennis eventually finds Johnny in the shelter. Although Johnny is delirious and in great pain, Dennis manages to coax him out into the open. Seeing the police, Dennis runs in the opposite direction to draw their attention. Dennis escapes across rooftops and tries to hide in a busy tram, but is eventually arrested. Johnny staggers away and falls over when a bus passes. Rosie and Maudie, two British women new to Belfast, assume he has been hit by the bus and take him home. They soon realise who he his, and when Rosie's husband comes home, he insists Johnny leave.

Johnny is helped by some passing British soldiers into the back of a horse-drawn cab and when the driver returns, he drives off without realising he has a passenger. When he sees Johnny, he leaves him barely conscious out in the rain, where he is found by Shell. Granny and Kathleen hide a gun and bandages when the police come to search the house. The Inspector warns Kathleen to stay out of it and after he leaves, Granny tells her to do the same. Kathleen, however, decides to go and find Johnny and get him on a ship. She visits Father Tom and finds him talking to Shell, who is prepared to 'sell' Johnny to them for a fee. After Shell leaves, she tells father Tom that she would rather die than live without Johnny.

Shell goes to get Johnny, but finds that he has made it as far as the local pub. There he runs into Lukey, who wants to paint Johnny and capture his dying expression. Shell and Lukey get into a fight and eventually the pub is cleared. The angry publican makes Lukey take Johnny away with him. Lukey takes him home and props him up in his studio. He begins to paint the portrait while his neighbour Tober gives him medical attention. Johnny eventually regains consciousness, although is increasingly prone to hallucinations.

Shell tries to take Johnny to Father Tom but only makes it part of the way before the police arrive. He leaves him hidden behind some bushes near the square and runs to the church. Kathleen meets him there and runs off to meet Johnny. The two embrace near the docks and she tells Johnny that she has passage for them on a ship. The two try to reach it, but he is too weak. When the police appear, Kathleen shoots in their direction and the return fire kills them both.