Therese

Thérèse is living in a provincial town, unhappily married to Bernard, a dull, pompous man whose only interest is preserving his family name and property. They live in an isolated country mansion surrounded by servants. Early in her marriage, her only comforts are her fondness for Bernard's pine-tree forest, which was her primary reason for marrying him, and her love for her sister-in-law and Bernard's half-sister, Anne. On Thérèse's honeymoon, she slipped away from Bernard's bed to throw away a letter from Anne in which Anne expressed her love for Jean, a Jewish student. Later, when Jean leaves Anne, Thérèse feels a sense of satisfaction and relief. However, Anne soon leaves. Desperately lonely and trapped, Thérèse accidentally learns that an increase in Bernard's medication makes him ill. While Anne nurses Thérèse's unwanted baby, Thérèse begins to experiment, taking advantage of his hypochondria and forgetfulness. Eventually she tries to poison him with arsenic, but the dose isn't fatal. Thérèse's forged prescriptions are then discovered. Thérèse is arrested, but Bernard refuses to press charges. She is acquitted when Bernard perjures himself for her at the trial and her politically influential father bribes a court official. On the way back to the country estate, she tries to think of an explanation to offer to Bernard. Unable to give Bernard a proper explanation, she allows Bernard to place her in a prison of his own devising. He locks her in a bedroom and allows her only cigarettes and wine, as she slowly wastes away. Much later, he frees her for a party at which the family gathers to meet Anne's new husband, and their friends are shocked at her sickly appearance and deterioration. Bernard then moves her to Paris. Still hoping to learn the motives for her crime, he listens to further explanations, but he cannot understand.The movie recounts in flashback the circumstances that led to her being charged with poisoning her husband.