Christine Costner Sizemore was an American woman who, in the 1950s, was diagnosed with multiple personality disorder, now known as dissociative identity disorder. Her case was depicted in the 1950s book The Three Faces of Eve, written by her psychiatrists, Corbett H. Thigpen and Hervey M. Cleckley, upon which the film of the same name, starring Joanne Woodward, was based. Sizemore went public with her identity in the 1970s.