Twelfth Night, or What You Will.

The tale begins when a brother and sister are separated in a shipwreck, but survive to be washed up on the shore of Illyria. The sister, Viola, disguises herself as a man and takes service with Duke Orsino, who has fallen in love with Lady Olivia. Entrusted with pleading on her master's behalf, Viola is utterly disconcerted to find that Olivia has fallen in love with her. Thus begins the confusion of this delightful comedy.