Isabella has a problem. Vicentio, the ruler of Vienna, has left Angelo in charge because, Vicentio says, he needs to leave the city on a diplomatic mission. Angelo is strict and has made fornication a capital crime. Claudio, Isabella’s brother, has gotten his girlfriend pregnant, and as a result he has been sentenced to death. Isabella, a novice nun, pleads to Angelo to have mercy and not execute her brother, but Angelo gives her a choice: Either Isabella has sex with him and does not tell anyone, or her brother dies.