As well as being the most revered and prolific writer of Gallic detective fiction, the creator of Inspector Maigret was an observer of human foibles, with a secret fascination for things sexual.

Roselyne Bosch has adapted Georges Simenon's En Cas De Malheur into a classy tale of love, desire, jealousy and betrayal.

A famous Parisian lawyer (Gerard Lanvin), married to a chic, elegant sculptress (Carole Bouquet), takes on the case of a young shoplifter (Virginie Ledoyen), who attempted to rob a jewellers with a toy gun. His colleagues don't understand. Why bother, when she's obviously guilty and can't pay the fees? He says he's bored and needs a challenge.

The girl comes from the same provincial town as he and from a similar underprivileged background. "I am her," he says. His wife knows, even before anything happens, that there is more to this than ennui and professional daredevilry, as does the girl's drug-dealing, bartending boyfriend (Guillaume Canet).

The performances are exquisite, the relationships played out with infinite subtlety, the feelings torn and mended and torn again. The girl's passion is too wild to tame, her heart fickle and free.

The director, Pierre Jolivet, juggles these conflicting emotions. Sex and love are intertwined. Violence lurks menacingly. The innocence is compromised, even if it existed at all. The film has perfect symmetry. Like haute couture, it is beautifully cut.