Twelfth Night — Act 5, Scene 1: Before OLIVIA's house.

At Olivia’s house, Fabian tries to see the forged letter that has fooled Malvolio, but the Clown refuses to hand it over. Duke Orsino then arrives with Viola and his attendants, and the Clown jokes with him before going inside to fetch Olivia. Antonio appears with officers, is recognized as Orsino’s enemy, and defends Viola for helping him, which Orsino dismisses as madness. Olivia comes out, argues with Orsino, and then reveals that she has married Sebastian, whom everyone mistakes for Cesario. Sebastian arrives and is identified as Viola’s twin brother. The truth comes out about the letter and Malvolio’s mistreatment, and the scene ends with the Clown’s song.