As Caligula opens, a group of Roman patricians are gathered in the imperial palace. The young emperor, Caius, known affectionately as Caligula (little boot), has disappeared following the death of his sister Drusilla. Joined by Helicon, an aide to the emperor, and Cherea, an author, the patricians praise Caligula as “exactly the emperor we wanted; conscientious and inexperienced.” Cherea, however, warns of the danger posed by an “artistic emperor.” Scipio, a young poet, enters to report on the search, leaving promptly when the discussion turns to Caligula’s successor.

A guardsman enters, announcing that Caligula has been sighted, and the stage clears. Caligula enters, becoming fascinated with his reflection in a mirror. Helicon returns and Caligula addresses him, expressing his desire for “the moon,” for “the impossible.” Helicon accepts Caligula’s quest and promises to help. Caligula exits. Scipio enters, accompanied by Caesonia, Caligula’s mistress; their passionate concern for the emperor contrasts sharply with Helicon’s detachment. To Helicon, Caligula is merely idealistic and therefore unpredictable.

Helicon exits and Caligula enters. Some patricians and the Intendent of the palace appear. In response to the Intendent’s concern over the Treasury, Caligula announces a plan to have the country’s wealthy men change their wills to make the state their beneficiary. These men will then be executed to replenish the imperial coffers. The patricians and Intendent are shocked; Scipio calls the plan “impossible . . . a lunatic’s pastime.” “An emperor’s vocation,” Caligula counters.

Cherea enters, but Caligula dismisses him. “I don’t like literary men and I can’t bear lies.” Cherea’s lie, according to Caligula, is to “attribute importance to people and to things,” when the truth is that “this world has no importance; once a man realizes that he wins his freedom.” Scipio, too, is dismissed, for “what is friendship?” Alone with Caesonia, Caligula asks for her support, which she pledges. Some patricians enter and Caligula gathers them around. Gazing once more at his reflection in the mirror, he acknowledges himself with a proud “yes . . . Caligula” as act 1 concludes.

The second act opens with Scipio and some patricians meeting secretly in Cherea’s house. Three years have passed, with Caligula’s oppression becoming more severe and senseless. Scipio’s father has been executed. One patrician’s son has been killed; another’s wife has been violated by Caligula. The group, armed, is starting out after Caligula when Cherea enters. He counsels caution. In time, he tells them, Caligula will be isolated from the masses not only by his deeds, but also by his “inhuman vision,” according to which life “means no more than a speck of dust.”

There are trumpet calls. Caligula enters, accompanied by Caesonia and Helicon. The Emperor proceeds to remind the patricians of his atrocities, then gratifies himself sexually (just offstage) with a patrician’s wife. He also orders the public granaries closed. Finally, he forces a fatal dose of poison down the throat of an unfortunate patrician and exits.

Scipio enters and is drawn into conversation first with Caesonia, then Helicon, who says “I know that you could kill Caligula and he wouldn’t greatly mind it.” Helicon exits and Caligula enters. Scipio asks Caligula if, like all men, he does not have some “secret solace” which provides relief “when life has wearied them beyond enduring.” Caligula responds: He does “have something of the kind . . . Scorn.”

Act 3 opens with the rhythmic clashing of cymbals and a thudding drum. As the curtain rises, the audience sees a platform set up in a room of the imperial palace. Caesonia and Helicon are on the platform. Some patricians and Scipio are sitting on...