Fabian asks the Fool if he can see the letter Malvolio wrote, but the Fool refuses to show it to him. Viola, Orsino, Curio, and other Lords enter and Orsino tells the Fool to fetch the Lady Olivia. The officers bring in Antonio and Orsino calls him a pirate. Viola sticks up for him, saying that he helped her fight Sir Andrew and Sir Toby. Antonio calls Cesario an ungrateful boy for not appreciating that he rescued him from the sea and brought him to the city. He also says that he has spent the past three months with the boy, but Orsino protests saying that Cesario has spent the last three months in his service. Olivia and her attendants enter, and she greets Cesario as her betrothed. Orsino declares his love, but she refuses him explaining that she is going to marry Cesario. Viola refuses her and she is confused. To prove that they are betrothed, she brings in the priest and he swears that they are betrothed. Orsino gets angry with Cesario because he thinks that he did agree to marry the girl he is in love with. Sir Andrew enters bleeding and saying that Cesario beat him up. Cesario denies it, but Sir Toby comes in bloody as well. Worried, Olivia sends Andrew, Toby, the Fool, and Fabian exit so they can fix any cuts they have. Sebastian then enters apologizing to Olivia for hurting her kinsman. Everyone is astonished to see Sebastian and Cesario together. Sebastian greets Antonio as a friend and tells him he was worried about him. Sebastian looks at Viola and says that he never had a brother, only a sister. Viola thinks that Sebastian is a ghost of her dead brother. Finally, Viola reveals herself, and Sebastian reveals to Lady Olivia that he loves her. He also says that Viola refused her because she was a woman. Orsino is delighted that Cesario is a woman, and asks her to put on women's clothing because he loves her and wants to marry her. She tells him that the captain who rescued her has them. Feste enters with Fabian, carrying the letter that Malvolio wrote, and gives it to Lady Olivia. She asks Fabian to read it, and after hearing him, tells him to fetch Malvolio. While waiting, Olivia talks to Viola (as herself) and when Malvolio enters, he declares that Olivia has wronged him. He gives her the letter he found, and she says that the letter was in Maria's handwriting. Fabian confesses the prank that they played and Olivia tells Malvolio it was just a prank. He promises revenge on the pranksters and leaves. Orsino plans to marry Viola and takes her off. The fool closes the play by singing a song.