The Honeymoon Killers is a 1970 American film written and directed by Leonard Kastle, and starring Shirley Stoler and Tony Lo Bianco. It tells the story of Martha Beck and Raymond Fernandez, the notorious "Lonely Hearts Killers" who murdered at least 12 women in the 1940s. The soundtrack is a selection from the works of Gustav Mahler. Martin Scorsese was originally hired to direct the film, but he was replaced due to creative differences with the producer.
Martha Beck is a sullen, overweight nurse who lives in a southern town with her elderly mother. To help her find a man, Martha's friend Bunny writes to a "lonely hearts" service, which results in a letter from Ray Fernandez of New York City. Overcoming her initial resistance, Martha corresponds with Ray. He visits Martha and seduces her. Later, Ray sends Martha a letter ending their "relationship" and Martha calls him, threatening to kill herself because she cannot live without him.
Moved by her devotion, Ray asks Martha to visit him in New York. There, Ray reveals that he is a con man who corresponds with lonely women with the intent to seduce and swindle them. Martha still proclaims her love for Ray, however, and she accompanies him as he moves from woman to woman. Posing as his sister, Martha can barely contain her jealousy as she watches Ray romance other women, though Ray promises her that he will never sleep with them. Ray marries a pregnant woman, Myrtle Young, and Martha gives her a fatal dose of pills after Myrtle aggressively attempts to sleep with Ray.