Cousin Bette is a poor and lonely seamstress who, after the death of her prominent and wealthy sister, tries to ingratiate herself into the lives of her brother-in-law, Baron Hulot, and her niece, Hortense Hulot. Instead, she finds solace and company in a handsome young sculptor she saves from starvation. However, the aspiring artist soon falls in love with another woman, Hortense, leaving Bette a bitter spinster. Bette plots vengeance on the family that rejected her and stole her only love. She slowly destroys the lives of those who have scorned her with the help of famous courtesan Jenny Cadine.