Shirley Ardell Mason (January 25, 1923 – February 26, 1998) was an Americanpsychiatric patient and commercial artist who was reputed to have multiple personality disorder, now called dissociative identity disorder. Her life was fictionalized in 1973 in the book Sybil, and two films of the same name were made in 1976 and 2007. Both the book and the films used the name Sybil Isabel Dorsett to protect Mason's identity, though the 2007 remake stated Mason's name at its conclusion.