Benoîte Groult, who became a leading French feminist and writer in the second half of her life, drawing wide attention with a sexually daring novel that explored an unlikely love affair between a Parisian intellectual and an uneducated Breton fisherman, died on Monday in Hyères, in southeastern France. She was 96.

Her death was confirmed by her publisher, Éditions Grasset.

Ms. Groult’s novel “Les Vaisseaux du Cœur (“Salt on Our Skin”), published in 1988, was branded pornographic in some literary circles because of its vivid depictions of an extramarital affair and female sexuality.

The book, set in France in the 1960s, examines the complex emotional dynamics of the couple’s relationship in which their raw desire for each other cannot overcome the wide social divide between them. They each end up marrying someone from a similar background yet they continue their affair for four decades.

In 1992 the novel was made into a film, directed by Andrew Birkin and starring Greta Scacchi and Vincent D’Onofrio. It was released in the United States as “Desire.”