Lothario Ray Fernandez (Tony Lo Bianco) cons lonely women out of money by promising marriage. When he meets nurse Martha Beck (Shirley Stoler), the two fall in love. Posing as brother and sister, the duo crosses the country swindling women -- and, when necessary, killing them. As their passions become more inflamed, their crime spree grows bloodier. This film is based on the real-life Lonely Hearts murders of the late 1940s.