A prison, colonial Jamaica. Three inmates decide to break out of prison: young and temperamental Smallboy Dowling, Sutlej, an intellectual, and the more cheerful Sonny. The day before they leave, Smallboy's mother, Mrs Dowling, visits. She is a religious woman who works as a hotel maid. Mrs Dowling tells her son the gossip in the town: among other things Dolly Green, Sutlej's ex-girlfriend and the mother of his child, is going to marry a rich, old, white man.

The next day, the men break out. Sutlej knocks the warden unconscious, but when it seems as though he is about to revive, Sonny strangles him. Out on the street, Sonny decides that he would be better off on his own and splits from the other two.

Sutlej and Smallboy sneak in to the offices of Randall, the richest black man in Jamaica. Sutlej knows that Randall started his fortune running brothels in Kingston and uses the information to persuade Randall to assist their escape plan. Sutlej wants him to provide them with new identities, an introduction to middle-class society and enough money to buy and stock a 10,000-acre farm. Randall agrees to the deal and installs the escaped convicts in one of the best rooms in the hotel.

Detectives arrive at the hotel to question Mrs Dowling about her son. Mrs Dowling has a gloomy foreboding that she will never see her son alive again. Meanwhile outside the hotel a peanut vendor has immortalised the story of Sutlej and Smallboy, now wanted for the murder of the warden, in a calypso.

Dolly Green visits Sutlej at the hotel. Sutlej wants his son to come with them to the farm. They argue vehemently. Dolly rejects his offer of reconciliation, telling him that his true son is Smallboy, heir not only to his fantasies but also to his bitterness.

Stung by Dolly's words, Smallboy and Sutlej leave the hotel in pursuit of their paradise island. Outside they run into Smallboy's mother who cries out to him thereby drawing the interest of nearby policemen.

Sutlej and Smallboy are pursued to the swamps. Sutlej takes some poison. Smallboy wants to take the poison too but Sutlej throws the bottle away. Sutlej wants him to stay alive and keep fighting for a better life. He writes a farewell letter in which he claims responsibility for the death of the warder.