The most popular novel by Gothic mystery and thriller writer Sheridan Le Fanu, Uncle Silas is one of the first of the "locked room" mystery genre, and served as the inspiration for Arthur Conan Doyle's The Firm of Girdlestone. Teenage heiress Maud Ruthyn lives in a mansion with her withdrawn father. She slowly finds out that a man named Silas Ruthyn, a reprobate with a dark mysterious past, is her uncle, although he is now apparently a good Christian. Her uncle's mansion holds a locked room where a man to whom Silas owed a great deal of money allegedly took his own life. Maud's father is steadfast in upholding his brother's innocence, but Maud herself grows increasingly fearful and unsure.