Twelfth Night is a comedy by William Shakespeare about a shipwrecked woman, Viola, who disguises herself as a man to work for Duke Orsino. Viola falls in love with the Duke but he loves Lady Olivia, while Olivia mistakes Viola's male identity Cesario for her lover. The play draws on several sources that involve themes of mistaken identity, gender roles, and love conquering all. It explores these themes in a witty and lighthearted way through the use of cross-dressing, clever dialogue, and romantic subplots that get resolved by the end of the play.