The opening scene sets the tone of a nightmarish, dehumanized, and machine-dominated world. In a drab and barely furnished bedroom, a slovenly looking Mrs. Zero engages in a wearying monologue directed at her husband, who is lying on the bed. Her refrain is how Mr. Zero has been a failure, holding the same dead-end job as a department-store clerk for twenty-five years. A henpecked husband, Mr. Zero finds his sole pleasure in peeping at an undressed prostitute in a room across the way. His wife has forced him, however, to report the girl to the police.
Scene 2 takes place in the department-store office where Zero works. He sits on a high stool face-to-face with Daisy Diana Dorothea Devore. She is calling out figures, which he enters into a ledger. Their thoughts, expressed in asides amid the chanting of numbers, are a lament for their failure to grasp the love they secretly feel for each other. Then Zero imagines his confronting his boss and successfully demanding a raise. His courage ebbs away, however, when the boss does not even know his name. The final blow is when the boss informs Zero that they are planning to install adding machines and thus will no longer need him. Losing control, Zero kills the boss by stabbing him with a bill file.
Scene 3 opens with Mrs. Zero at home, impatiently waiting for her husband. She snatches away his unfinished dinner when guests arrive—six couples dressed alike and having numbers instead of names, Mr. and Mrs. One, Mr. and Mrs. Two, and the like. Speaking in robot like fashion, all express the same views and the same prejudices: "Politics is a man’s business"; "Woman’s place is in the home"; "America for the Americans." The talk is interrupted by a policeman ringing the doorbell. Zero says that he has been expecting the officer: He has broken the rules and knows that he must pay the penalty.
Scene 4 is Zero’s trial. Except for the announcement of the jury’s verdict at the end, the scene consists of a stream-of-consciousness monologue by Zero to the jury. He jumps back and forth from one recollection to another as he relates the repeated frustration of his hopes and dreams. He admits his guilt but blames the boss for firing him and then continuing to talk until Zero lost control. His plea that he is "a regular guy like anybody else" makes no impression. The jurors—the same people who were the guests at his party—rise and shout in unison, "GUILTY!"
Scene 5 was omitted from the 1923 Theatre Guild production and the published version that came out the same year. It was first performed in the 1956 New York revival of the play; the text appears in a 1965 Hill and Wang edition,
Three Plays. Zero is caged like an animal in a zoo while a guide describes him as "the North American murderer. Genus homo sapiens. Habitat North America . . . [with] the characteristics which are typical of his kind." As a typical American, he is eating ham and eggs. When offered an eight-course dinner of his choice as his final meal, he lacks the imagination to break out of his routine and so orders eight courses of ham and eggs. Toward the end of the scene, a strange figure who identifies himself as the Fixer from the Claims Department is introduced. He rebuffs Zero’s desperate pleas for "another chance" with the reply that a man is more expensive to keep up than an adding machine.
While a pair of assistants drag Zero off for execution, the Fixer sits reading the newspaper comics.
Scene 6 is set in a graveyard. Judy O’Grady, the prostitute whom Zero had reported to the police, enters with a young man and sees an opportunity to have her revenge by engaging in sexual intercourse on Zero’s grave. The young man balks, and the two go. Then Zero arises from his grave to exercise and meets another corpse, Shrdlu. Shrdlu had killed his overprotective mother in a fit of rage and now expresses his longing to be punished for his crime. Suddenly a head pops up from a grave, tells Zero and Shrdlu to "shut up and let a guy sleep," and calls down for the loan of a companion’s head. After he tosses the skull at Zero and Shrdlu but misses, the head exclaims "Ho-hum! Me for the worms!" and disappears as the curtain falls.
Scene 7 features the green meadows of the Elysian Fields (Heaven). Shrdlu continues to bewail his failure to be punished for his crime. Like Shrdlu, Zero cannot shake the Puritan morality that had shaped him on earth. When he meets Daisy, who has committed suicide because of her unhappiness over Zero, the two acknowledge their love for each other, kiss, and then dance wildly. Hearing someone approach, however, Zero tells Daisy to fix her hair and pull down her skirt. When Shrdlu tells them that they can stay together in the Elysian Fields without getting married, Zero is shocked at the thought of such a breach of propriety. Even more shocked when he learns that the place is filled largely with drunks, thieves, and vagabonds, he expresses his wish to return to earth and the world of "respectable" society. There is a final exchange between Daisy and Shrdlu. When he asks whether she will remain in the Elysian Fields, Daisy answers that, with Zero gone, it makes no difference and thus she "might as well be alive."
In the final scene, Zero is operating a giant adding machine somewhere in Limbo, when Lieutenant Charles informs him that he must stop and return to earth to begin again as a baby. When Zero wonders whether he had been a king in a previous life, Charles informs him that in all of his past incarnations he had been a slave—and that he had in fact retrogressed with each successive return to earth. When Zero balks at going back, Charles finally overcomes his resistance by promising him that a beautiful young girl named Hope will accompany him and help him forget. The play closes with Zero’s place being readied for a newcomer while Charles muses, "Hell, I’ll tell the world this is a lousy job!"