Ann Sutton (Gene Tierney), the wife of psychoanalyst Dr. William Sutton (Richard Conte) is a kleptomaniac. She is rescued from humiliation and arrest by David Korvo (Jose Ferrer), a mysterious hypnotist who ingratiates himself with her. With self-admitted sociopath tendencies, David Korvo is up to something, using Ann for his own purposes. She is too embarrassed to tell her husband about the problem. Ann meets Theresa Randolph (Barbara O’Neil) who warns her that Korvo is not to be trusted, but to no avail. She begins to see Korvo weekly for hypnosis treatments, but she may have been given some unsavory post-hypnotic suggestions for murder.