The Three Faces of Eve (1957)
The Three Faces of Eve is a 1957 American film adaptation based on a book by psychiatrists Corbett H. Thigpen and Hervey M. Cleckley, who also helped write the screenplay. It was based on their case of Chris Costner Sizemore, also known as Eve White, a woman they suggested might suffer from multiple personality disorder. Sizemore's identity was concealed in interviews and this film, and was not revealed to the public until 1975.
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