Portrait in Black

As the health of tyrannical but gravely ill shipping tycoon Matthew Cabot (Lloyd Nolan) declines, he relies on pain medicine injected by his physician, Dr. David Rivera (Anthony Quinn). What Cabot doesn't know is that his frustrated wife, Sheila (Lana Turner), is having an affair with the doctor and has conceived a plan to do away with her husband. David agrees to go through with the murder, but threatens to confess their crime when Sheila begins receiving anonymous letters from a blackmailer.