A group of lords and townspeople is assembled at the city gates. The Duke enters, greets Angelo and Escalus, and thanks them for their service. Friar Peter brings Isabella forward, and she asks the Duke for justice. He tells her to deliver her complaint to Angelo, but she responds that she needs the Duke’s help, for Angelo is the “devil.” Angelo tries to interrupt, but she continues, calling him “an adulterous thief, an hypocrite, a virgin-violator.” The Duke asks for Isabella to be sent away, as she appears to be insane.
Isabella shows she’s not completely deferential to society’s restrictions by speaking out publicly about a taboo. Of course, it shouldn’t be forgotten that Isabella has been put in this situation by the Duke’s machinations, but her self-assertiveness is still impressive. Interestingly, though nearly every piece of the Duke’s plan has fallen into place, he does not abandon his play-acting. His rationale for initially dismissing Isabella as insane is unclear, though it may help to get Angelo to further implicate himself.
Isabella continues to protest. The Duke then remarks that Isabella’s madness seems strangely reasonable, and asks her to voice her accusation. Isabella announces that she is the sister of Claudio, who has been executed for fornication. Lucio interrupts to corroborate the story, and the Duke curtly tells him to be silent. Isabella continues and says she begged Angelo to free her brother, but he said he would do so only if she had sex with him. She says she eventually yielded to his demands and gave up her virginity, but Angelo ordered Claudio’s execution in spite of this. The Duke rejects Isabella’s testimony as lies and urges her to confess the truth.
The Duke’s condemnation of Isabella as a liar has several layers of meaning. To onlookers utterly unaware of Angelo’s actions, the Duke simply appears to be defending his lieutenant against spurious accusations. To those with more information, however, the Duke’s words are actually the outright truth: Isabella is lying by claiming to have sacrificed her virginity herself, rather than admitting that Mariana did so for her. This clearly shows that Isabella values the actual state of being chaste more than she values the social appearance of chastity—precisely the opposite of Angelo’s priorities.
Isabella sticks to her story, and the Duke orders her sent to prison. Before she is sent away, the Duke asks her if anyone knew of her plan to testify against Angelo. Isabella answers that Friar Lodowick did. The Duke asks if anyone knows this friar; Lucio responds that he knows the friar and finds him distasteful. Lucio claims that he has disciplined the friar for speaking ill of the Duke.
Here, the scene grows even more convoluted and suspenseful. Furthermore, by falsely and gratuitously denouncing Friar Lodowick, Lucio makes himself into a more unsympathetic and duplicitous character—one who deserves a just punishment in this public venue.
Friar Peter comes forward and agrees with the Duke that Isabella is lying. The Duke inquires if he is familiar with Friar Lodowick, and Friar Peter says that he knows Lodowick to be an honorable man, who never impugned the Duke as Lucio alleged. Friar Peter claims that Friar Lodowick has taken sick and asked him to testify on his behalf. He says that this testimony will disprove Isabella’s testimony.
Friar Peter’s claim that he can disprove Isabella’s testimony makes it seem as though he may have the end goal of exonerating Angelo. This shifts the momentum of the scene in Angelo’s favor, and leaves the audience in further suspense about whether or not justice will be served.
Isabella is taken away by guards, and Mariana comes forward as a witness. She wears a veil, which the Duke asks her to remove. She replies that she will only show her face when bidden to by her husband. The Duke asks her if she is married, a maid, or a widow, and she denies all three. Mariana clarifies this seeming paradox by saying that she has slept with her husband, though her husband does not know it. Angelo, she says, is this husband, though he believed her to be Isabella when they had sex.
Mariana occupies a gray area: none of her potential identities are clear-cut and condoned by society. The inappropriateness of her situation underscores Angelo’s wrongdoing. By callously disregarding his social obligation to his fiancée, Angelo deeply wronged Mariana. And by violating yet another social proscription, this time against premarital sex, Angelo places Mariana in the still less acceptable social limbo that she occupies now. In this way, Mariana’s inability to fit into society actually illustrates the way that Angelo’s actions completely violate social standards.
Angelo, scandalized, asks Mariana to show her face, and she complies. The Duke asks Angelo if he recognizes her, and Angelo tells the story of their engagement, attesting that he has not seen her in five years. Mariana counters that he had sex with her that Tuesday night. Angelo tells the Duke that Mariana and Isabella must be lying at the will of some unknown third party. The Duke denounces Friar Peter and the women and tells the Provost to bring Friar Lodowick. The Duke then tells Escalus to proceed with the trial while he leaves.
The Duke’s denunciation of Friar Peter gives the appearance that he still sides with Angelo. After all, the testimony Friar Peter offered to disprove Isabella only ended up affirming her condemnation of Angelo’s character.
Escalus summons Isabella and, at Lucio’s suggestion, questions her in private. The Duke, back in his friar’s disguise, then reappears with the Provost. Escalus asks the disguised Duke if he conspired to have the women testify against Angelo. Indignant, the disguised Duke asks to see the Duke, but Escalus responds that the Duke has given him authority to oversee the trial. The disguised Duke responds by calling the Duke unjust, and Escalus angrily threatens to have the disguised Duke tortured for saying such things. Lucio attests that the disguised Duke slandered the Duke, but the disguised Duke protest that he loves the Duke and it was in fact Lucio who spoke slanderously. Escalus orders the disguised Duke imprisoned, and the Duke asks the Provost not to cooperate. At Angelo’s behest, Lucio hurls insults and removes the disguised Duke’s hood, revealing the Duke’s true identity.
Finally, the Duke’s overarching plan has been revealed. At this point, it is clear that characters will be brought to justice for their misdeeds. The various disconnections between appearance and reality that had been present throughout the play—the Duke’s disguise, Lucio’s deceptive slander, and Angelo’s feigned virtue—are now ready to be rectified.
The Duke asks that Friar Peter, Mariana, and Isabella be released from custody and requests that Lucio be restrained. He then asks whether Angelo can say anything to defend himself. Angelo admits his guilt and requests a death sentence, but the Duke sentences him to marry Mariana. Angelo exits with Mariana. The Duke then apologizes to Isabella that he did not intervene sooner to save Claudio’s life, but tells her to take comfort in the peace her brother has found in death.
Angelo’s regret and shame are clear in his request for a death sentence, and like his earlier confessions of torment, his quick admission of guilt makes him a slightly more sympathetic character. Even as justice is being served, however, the Duke bizarrely withholds from Isabella the truth about her brother’s fate. This misinformation seems rather unnecessary, and a continuation of the somewhat cruel deception he began in Act 4, Scene 3.
Angelo, newly-married, returns, and the Duke proclaims that he shall be executed in Claudio’s place, as “measure still for measure.” Mariana, not wanting to be widowed, begs the Duke to reconsider and says she does not desire any other husband. Mariana enlists Isabella to help beg the Duke to pardon Angelo. Isabella asks the Duke to let Angelo live, as his bad intentions never came to fruition.
Mariana’s willingness to marry Angelo, malevolent as he may be, illustrates just how dependent she is on obtaining an acceptable social station. Isabella’s miraculous choice to forgive Angelo illustrates that she has indeed achieved a more compassionate vision of sin than the rather strict outlook she had earlier. Furthermore, her willingness to forgive highlights just how unreasonable Angelo’s unwillingness to forgive Claudio was.
The Duke does not respond to the women’s requests, and instead asks the Provost why Claudio was beheaded at an unusual time of day. The Provost answers that the act was carried out on private commands, and the Duke strips him of his rank for obeying anything other than an official warrant. However, the Provost says he has kept Barnadine alive, against these orders. The Duke summons Barnadine, and the Provost returns with Barnadine, Juliet, and Claudio. Claudio’s face is obscured. The Duke asks who the concealed prisoner is, and Claudio is revealed. The Duke pardons Barnadine, Claudio, and Angelo; and then asks for Isabella’s hand in marriage. He then tells Lucio that, as punishment for slandering the Duke, he will be forced to marry the prostitute he impregnated. The Duke ends the play with a speech commending the characters’ virtue and hoping for a pleasant married life with Isabella.
This conclusion brings a typical “marriage plot” resolution to the play and allows justice to be served. Perhaps the most surprising aspect of this ending is the lenient pardon Angelo is granted. However, it is in many ways a perfectly appropriate “measure for measure” penalty for Angelo’s misdeeds. After all, as Isabella points out, Angelo’s machinations never actually ended up harming anyone, despite his intentions; he has been punished by having to suffer the shame that he has inflicted on others, but no further. Lastly, though Isabella’s response to the Duke’s proposal is often left to be decided by the director of the play, it should be noted that she seems to have very little room to choose her own fate, as the Duke’s proposal is likely a difficult one to refuse. In this sense, Isabella can be said to spend the entirety of the play governed by societal expectations for her conduct, rather than able to act as a free agent and make her own decisions—a discouraging illustration of the lack of freedom for women in this Shakespearean setting.