the action of the comedy takes place in a fictional country - illyria. the ruler of illyria, duke orsino, is in love with countess olivia. countess in mourning due to the death of her brother and father.
the twins - brother and sister sebastian and viola, having suffered a shipwreck, found themselves in illyria and lost each other. viola, dressed in men's clothes, appears at the court of orsino. the duke liked the young man named caesario (this name viola took for himself), and he brings him closer to him. viola falls in love with the duke. orsino does not notice this and gives his new page an order to go to olivia and try to woo her.
her uncle toby lives at olivia's court, a drunkard and a merry fellow. he spends time in joint drinking bouts with sir andrew, who also unsuccessfully seeks the attention of olivia. caesario is seeking an audience with olivia and sending her news from orsino. the affair ends unexpectedly: olivia politely pays tribute to the virtues of the duke, but falls in love with a glance with the messenger of the duke.
in the meantime, sebastian appears in the city, mourning his sister, considering her dead. begins a whole series of misunderstandings. brother and sister, extremely similar to each other, all confused.
olivia, confusing sebastian with viola, asks him to marry her. he was embarrassed, but agreed, and they got married. orsino resigns to the loss of olivia and wants to see viola in a woman's dress.
