Reminiscent of the medieval legend of Tristan and Iseult but set among young middle-class people in a provincial city, it tells the story of a fatal romance between a loving husband (Gérard Depardieu) and the attractive woman (Fanny Ardant) who moves in next door.

[2] Bernard lives happily with his wife Arlette and young son Thomas in a village outside Grenoble.

Bernard and Mathilde are shocked at meeting each other because years before, when both single, they had a stormy affair that ended painfully.

At first Bernard avoids Mathilde, until a chance meeting in a supermarket reawakens long-buried passions and soon, while openly good neighbours, in secret they pursue an affair.

But the rejected Mathilde then cracks and, after publicly collapsing at the tennis club, is hospitalised with depression.