Upon his entry, the duke finds Mariana at her home at Saint Luke's, listening to a boy singing a love ballad. Isabella soon arrives, and Mariana leaves the two to discuss their plans. She returns to meet Isabella and then goes aside with her while Isabella outlines the duke's idea of a substitute bed partner. Mariana agrees to the plan upon the duke's assurances of its propriety.
Given the choice of serving a prison term or becoming an executioner's assistant, Pompey chooses the latter, exiting with Abhorson to learn his new trade. The provost informs Claudio that he is to die on the following day, along with a condemned murderer. The duke arrives, expecting to hear of Claudio's pardon, only to be on hand as a letter is received from Angelo urging an early morning execution. The duke, however, persuades the provost to spare Claudio, sending the murderer's head in his place.
In his new trade as executioner, Pompey finds many of his former customers housed in the prison. At Abhorson's command, he calls Barnardine to be executed, but he refuses his execution. The duke enters and attempts to persuade Barnardine to accept his fate, but the prisoner merely reiterates his lordly refusal and returns to his cell.
Disturbed by Barnardine's unreadiness to die, the duke is relieved when the provost arrives with a solution. Another prisoner, similar to Claudio in coloring and age, has died of a fever. It is agreed that his head will be a substitute, and Barnardine will be hidden along with Claudio. When Isabella arrives, the disguised duke allows her to think that her brother's execution has gone forward. He tells her that the duke is returning and she must be present at the gates along with Angelo in order to reveal the truth and have her revenge. Lucio arrives, expressing honest grief at Claudio's death. Isabella departs, and Lucio attaches himself to the disguised duke, slandering the absent ruler as they leave together.
Escalus and Angelo are confused by the letters they have received from the duke, each contradictory. Now, on the verge of a return to the city, the duke sends word that they should meet him at the gates, giving advance notice that any with grievances should be there also. Angelo considers the possibility that Isabella may take this opportunity to accuse him but concludes that her shame and her inability to prove her claims will prevent her.
Giving some letters to Friar Peter, the duke asks him to deliver them and to call Flavius, Valentinus, Rowland, and Crassus to him. Varrius arrives as the friar is going off on his mission. The duke greets him and tells him other friends are expected, and the two walk off together.
Isabella describes to Mariana what the duke expects of them in the coming scene at the gates, and Friar Peter leads them away to accuse Angelo.
The love song with which Scene 1 opens is much admired as one of Shakespeare's greatest. Mariana, however, is somewhat embarrassed to be found listening to music and explains to the duke that it appeals to her grief rather than her gaiety. One of the inconsistencies of the play is the apparent familiarity of Mariana and the disguised duke. Although he has only been masquerading for a few days as a friar, she addresses him as though he had been her spiritual counselor for some time. Sending away the boy who has been singing for her, she says, "Here comes a man of comfort, whose advice / Hath often still'd my brawling discontent" (8-9). When the duke asks Mariana to allow him a private discussion with Isabella, she replies, "I am always bound to you" (25), as though speaking to an old friend. And again, when the duke tells her he respects her, she answers that she knows it and has found it to be true, suggesting a long-term relationship. The reader is left to speculate that the play was rewritten hastily with resulting inconsistencies.
Another indication of some confusion of the original is the duke's brief soliloquy, spoken while Isabella is persuading Mariana to lend herself to the scheme for Angelo's deceit. While the duke speaks only six lines, Isabella convinces a young woman whom she has just met to have sexual relations under bizarre circumstances with a man who has spurned her. The plan is a strange one, yet the woman gives her consent in a period so short that it would hardly be possible for Isabella to relate even a sketch of the reasons behind the deceit. The duke's lines themselves are strange since they have no bearing upon the current scene, alluding to the deceitful gossip to which persons in great places are subject. The lines in fact seem more appropriate to the duke's reactions in the previous scene to Lucio's falsehoods. It appears that some mix-up has occurred to confuse the scene.
In any case, Mariana agrees to the plan when the duke sanctions it. Significantly, the duke repeats his assurances that the scheme is not immoral or dishonorable since Angelo is Mariana's "husband on a pre-contract" (72).
In the opening lines of Scene 2, where Pompey changes his trade as a bawd for the art of execution, Shakespeare comments ironically on the society in which the latter is an honorable trade. A prisoner and bawd advances himself by becoming an executioner. Abhorson regards his trade as a "mystery"; Pompey is skeptical, and the provost remarks dryly that the two "weigh equally. A feather will turn the scale" (31-32).
After the brief comic interlude, Claudio is called to learn of his execution the following day at eight in the morning. He accepts his fate calmly, apparently at ease with his soul. The provost is still very much in sympathy with his case.
The duke enters to assure himself that Angelo's end of the bargain has been carried out. The reprieve has not yet arrived, but the duke ironically defends his deputy by telling the provost that "his life is parallel'd / Even with the stroke and line of his great justice . . . were he meal'd with that / Which he corrects, then were he tyrannous" (82-87). The truth, of course, is that the duke is well aware of Angelo's own shortcomings in the vice he is so determined to punish.
Angelo's crime is compounded by treachery. He writes the provost to execute Claudio four hours earlier than his original time and to deliver the head to him. In a sense, Angelo's treachery parallels that of the duke, Isabella, and Mariana. He is deceived by a surrogate bed partner, and he, in turn, deceives the conspirators by reneging on the promised pardon.
The duke, however, forestalls the execution by arranging to have Barnardine, conveniently invented for the purpose, beheaded in Claudio's place. Isabella and the duke will have the last laugh by providing a substitute head to the deputy. The provost is at first leery of such a risky deceit, but having seen the duke's own seal and a letter in his hand, he is convinced. The duke has arranged to make Angelo believe that he will never return to power: Angelo's tyranny is complete.
In Scene 3, the similarity between Pompey's old trade and his new one is underlined once more when he looks about himself in the prison to discover that his clientele is very much the same. When he calls Barnardine from sleep to his execution, Pompey's manner is unchanged. He is still very much the clown: "Pray, Master Barnardine, awake till you are executed, and sleep afterwards" (34-35).
But Barnardine refuses his execution: "You rogue, I have been drinking all night; I am not fitted for't" (46-47). Shakespeare makes him a vulgar and endearing character. In prison, under sentence of death and called to his execution, he is still very much on his dignity. He refuses to put himself to the inconvenience of being executed. He treats his executioners as if they were his servants, dismissing them in a high-handed way. The critics speculate that having created Barnardine for the purpose of dying in Claudio's place, Shakespeare took such a shine to the fellow that he could not destroy him--hence the creation of yet another character, one Ragozine, already dead of a fever when we first hear of him, who provides the substitute for Claudio's head. The duke, too, has apparently become attached to Barnardine and arranges with the provost to have him hidden away along with Claudio.
Setting the stage for the play's final scene, the duke informs the provost of his plans. He will write to Angelo, informing him of his return and desiring to be met publicly "at the consecrated fount / A league below the city" (102-103). A certain coldness enters his tone when he adds, "and from thence, / By cold gradation and well-balanc'd form, / We shall proceed with Angelo" (103-5). Though addressing the provost, he seems almost to be speaking to himself, anticipating the ironic justice that Angelo will meet at his hands.
Critics have argued that the duke's deceit of Isabella in allowing her to think her brother's death has been carried out is a cruelty that must reflect upon his character. It seems more likely that the deceit is merely a necessity of plot if the play's theme of mercy is to be carried out. Crucial to the interpretation of the last scene is Isabella's conviction that Angelo has not only used high office for his lust but that, having done his will, he has cheated on his bargain, causing her brother's execution. Through the duke's deceit, Isabella is convinced that Angelo is not only evil but without mercy himself. She has no reason to save her tormentor except mercy. If she were aware that her brother still lives, her mercy would be of a lesser quality since it would demand little of her.
The jesting Lucio arrives, for once serious and genuinely saddened by Claudio's supposed death. Upon Isabella's departure, however, he reverts to his whimsical slanders of the duke's character. And again, he delivers his witticisms ironically to the duke himself. With double irony, Lucio comments, "if the old fantastical duke of dark corners had been at home, he had lived" (164-65). Claudio does, in fact, live, and the duke is at home. Furthermore, Lucio has been most accurate in his reference to the "dark corners" since the duke's disguise is a form of hiding. Lucio's confession that he has gotten a whore with child foreshadows the punishment that the duke will lay down in return for his irreverence.
In Scene 4, in a soliloquy, Angelo reveals his reason for ordering Claudio's execution, contrary to his agreement with Isabella. Released, Claudio might, in time, have taken revenge. Angelo's conscience is bothering him. He regrets that Claudio is dead. His violation of Isabella amazes him. The fear that she may expose him drives him to consider the odds, and while he reasons that he is safe from her, he is still uneasy: "Alack, when once our grace we have forgot, / Nothing goes right: we would, and we would not" (36-37).
In Scene 5, there is strong evidence that the play is not intact. The friends whom the duke sends for here do not appear anywhere in the play, and Varrius, though he is listed in the actors of the final scene, does not speak. The purpose of the letters the duke refers to is not clarified here or elsewhere. Plainly some confusion occurred in the publication of this play, with sections omitted or perhaps two versions mistakenly put together. The scene does nothing by way of advancing the action or portraying the characters of the play as we have it.
In Scene 6, the duke, it appears, has advised Isabella to accuse Angelo as if she herself had yielded to his demands. Further, he has told her that he may at first appear to speak against her, but all will be right at the outcome. Friar Peter urges them to take their places at the gates.
The duke's plans for the next scene are revealed to the audience to the extent that there will be no question of the duke's loyalty to Isabella. The scene arouses the audience's curiosity, implying that there are yet unexpected events to come, and acts as an introduction to the final scene, building the audience's expectation toward the imminent confrontation.