Act 5 Scene 1
At the city gates, the ‘returned’ duke greets Angelo and Escalus. Friar Peter urges Isabella to kneel for her petition. She does, speaking passionately for 'justice, justice, justice, justice!' and calling Angelo 'a virgin-violator'. Angelo accuses her of turning mad because of her brother’s death and the duke has her arrested. Isabella mentions ‘Friar Lodowick’ (the duke’s disguise) and Lucio adds that he heard Friar Lodowick slander the duke. Isabella is led away and Mariana enters, veiled. Mariana claims that Angelo is her husband and that he has 'known' her body. Angelo confesses he knows Mariana and explains their broken engagement, but says she and Isabella must be ‘instruments’ in someone else’s plot. ‘Friar Lodowick’ is sent for and the duke explains that he must leave for a while. He returns, disguised as the friar and claiming to be an outsider who has watched 'corruption boil and bubble' in Vienna. Lucio accuses him of slander against the duke and pulls his hood off, only to reveal his true identity. The duke has Lucio arrested. Angelo confesses his crime and asks to be sentenced to death, but the duke sends him away to be married at once to Mariana.
The duke apologises to Isabella for Claudio’s death, saying that he could not reveal his identity before and that Claudio died sooner than he expected. Angelo and Mariana are brought back in, married. The duke orders that Angelo should be executed like Claudio: 'Like doth quit like, and measure still for measure'. Mariana begs Isabella to join her in pleading for Angelo’s life. Isabella agrees, saying that Angelo’s 'behaviour was sincere' until he met her. The duke then reveals Claudio, still alive. The duke pardons both him and Angelo and punishes Lucio by ordering him to marry the woman that he made pregnant, despite Lucio calling her a 'whore'. The duke asks Isabella to marry him but she does not answer.