Chris Costner Sizemore was an American woman known for her unique psychological condition. Born on February 4, 1923, she was diagnosed with Dissociative Identity Disorder (formerly known as multiple personality disorder), which led to the development of several distinct personalities. Her experiences were documented in the book "I Am Chris," written by Dr. Thigpen and Dr. Cleckley, who treated her. Sizemore's life and struggles with her condition gained significant attention, leading to her becoming a subject of study in psychology. Her story was later adapted into a film titled "The Three Faces of Eve," which further popularized her experiences and raised awareness about mental health issues.