The play's plot features its protagonist, Duke Vincentio of Vienna, stepping out from public life to observe the affairs of the city under the governance of his deputy, Angelo. Angelo's harsh and ascetic public image is compared to his abhorrent personal conduct once in office, in which he exploits his power to procure a sexual favour from Isabella, whom he considers enigmatically beautiful. The tension in the play is eventually resolved through Duke Vincentio's intervention, which is considered an early use of the deus ex machina in English literature.