This last act, which consists of only a single scene, takes place on a street in front of Olivia's house. Feste is reluctantly carrying Malvolio's letter to Olivia (pleading Malvolio's sanity), but Fabian is trying to discourage him from reading it. Feste, needless to say, is in no great hurry to deliver it.
Duke Orsino, Cesario (Viola), Curio, and others enter, and Orsino has a few words with Feste; he is pleased with Feste's quick wit and gives him a gold coin and tells him to announce to Olivia that he is here to speak with her and, furthermore, to "bring her along"; if he does, there may be more gold coins for Feste.
Cesario (Viola) sees Antonio approaching with several officers and tells Orsino that this is the man who rescued him from Sir Andrew earlier. (Antonio, of course, is still under arrest). Orsino remembers Antonio well; when he last saw Antonio, the sea captain's face was "besmeared / As black as Vulcan in the smoke of war." Antonio was the captain of a pirate ship then and did great damage to Orsino's fleet. Yet despite their past differences, Orsino remembers Antonio as being a brave and honorable opponent.
When he is asked to explain how he happened to be in Illyria, Antonio explains to Orsino that he is the victim of "witchcraft" — that is, he saved Cesario's life, and then this "most ingrateful boy" would not return the purse of money which he lent him earlier.
At this instant, Olivia makes a grand entrance with her attendants. When Orsino sees Olivia entering, he says that "heaven walks on earth." He tells himself that "this youth" (Cesario) "hash tended" him for three months; Antonio's words, of course, are impossible.
