The Seducers (1962)

Jean Wells (Dierking) believes she kills a man during a hit-and-run one evening. A man named Joe (Saegers)appears and, in exchange for keeping silent about the murder, blackmails Wells. Wells begins to doubt the accident and struggles with her sanity. She attempts suicide but is stopped by Joe, who informs her that the man is not dead and that her husband is trying to drive her crazy. Wells is pushed to the limit of her sanity with the ensuing plot twists.