The play is divided into 8 scenes. Scene 1 takes place in the fireman's forecastle of a cruise ship, where they sleep. Their racks resemble the bars of a cage. They are sailing from New York, where Yank and the other firemen are talking and singing drunkenly. Yank is shown to be a leader among them. Other featured characters are Long, a socialist, and Paddy, a particularly drunken Irishman.
Scene 2 takes place on the deck, where Mildred Douglas (the rich girl) and her aunt are talking. They are almost constantly arguing.
Scene 3 takes place in the stokehold. Yank and the other firemen take pride in their work. When Mildred comes to visit the stokehold, Mildred hears Yank cursing. When he turns around and she sees him, she is so shocked by him she calls Yank a filthy beast and faints.
Scene 4 also takes place on the ship. Yank is very depressed and the other men try to understand why.
In scene 5, Yank and Long go to 5th Avenue in New York. Yank argues with Long about how best to attack the upper class. Long leaves, fearing arrest, and Yank is arrested after attacking a Gentleman.
Scene 6 takes place at the prison at Blackwell’s Island. Yank tells the prisoners his story and one of the prisoners gives him an article about the Industrial Workers of the World. Yank tries to escape.
Scene 7 takes place at the IWW office that Yank goes to after his month in jail. They are happy to have him at first because there are not many ship firemen in the union – but he is thrown out after he says that he wants to blow up things, and they think he is a spy.
Scene 8 takes place at the zoo, when Yank is crushed after trying to talk to an ape and releasing it from its cage.