In the south-west of France, in the late 1920s, Thérèse Laroque agrees to a marriage of convenience between wealthy families by marrying Bernard Desqueyroux, a bourgeois landowner. They then settle on his family’s property, located in a vast area stretching over acres of pine forests. Bernard is a local man with a passion for hunting and defending with conviction the family traditions.

However, Thérèse is quickly stifled by the monotony of her married life. She gives birth to a daughter (Marie), but her boredom seems to grow every day; she is looking “somewhere else”. Bernard suffers from an unspecified condition for which he is prescribed arsenic. Thérèse takes the opportunity to attempt to poison her husband, but in forging a prescription, she is discovered. In addition to being dishonoured by her own family, she is disowned by her husband’s.

She faces justice for the alleged murder attempt until her husband and in-laws, who intend to keep up appearances within their provincial society, make up their own version of what happened. The case is dismissed and Therese is confined to the house. Eventually she is allowed to leave and live in Paris on the understanding that she will only return for weddings and funerals.