On a gloomy evening in 1945, an old woman by the name of Thérèse tells the tale of her life. Back in 1882, Thérèse settles in Châtillon with her fiancé Firmin. Pregnant and tired of her job as a waitress she and Firmin move in with Mrs. Numance, who is a generous middle-class women. During their time together, the two women develop a close mother-daughter relationship. But when Firmin betrays Mrs. Numance's trust, the three fall into ruin, leading to Thérèse arranging his murder.