Twelfth Night, or What You Will is a comedy play written by William Shakespeare. The story follows a young woman named Viola who disguises herself as a man named Cesario after being shipwrecked in Illyria. She falls in love with Duke Orsino, who in turn is in love with Countess Olivia. Olivia, however, falls in love with Cesario, not knowing that he is actually Viola in disguise.
Meanwhile, Olivia's uncle, Sir Toby Belch, and his friend Sir Andrew Aguecheek, play pranks on Olivia's steward, Malvolio. They convince him that Olivia is in love with him and make him act foolishly in front of her. Eventually, Viola's twin brother, Sebastian, arrives in Illyria, causing confusion as people mistake him for Cesario.
Twelfth Night explores themes of love, mistaken identity, and gender roles. The play culminates in a series of revelations and reunions, with Viola revealing her true identity and marrying Duke Orsino, while Olivia marries Sebastian. The title refers to the twelfth night of Christmas, a time of revelry and misrule, reflecting the chaotic and comedic events that unfold in the play.