The year is 1926. In the Landes region, free-spirited Thérèse Larroque, the daughter of a wealthy pinery owner and radical-socialist politician, marries Bernard Desqueyroux, another pinery owner. Although she does it half-heartedly, she thinks that marriage may help her to "sort out all the ideas in her mind". But her disappointment proves great. While Thérèse stifles in her husband's beautiful residence among stiff in-laws who do not think high of her, ideas keep on roaming her mind, with potentially tragic results.