Agatha Christie was a mystery writer who was one of the world's top-selling authors with works like Murder on the Orient Express and The Mystery of the Blue Train. Born on September 15, 1890, in Torquay, England, Agatha Christie published her first novel, The Mysterious Affair at Styles, in 1920, and went on to become one of the most famous writers in history, with mysteries like Murder at the Vicarage, Partners in Crime and Sad Cypress. She sold billions of copies of her work, and was also a noted playwright and romance author. She died on January 12, 1976.