"Fatal Attraction" director Adrian Lyne again shows adultery as the driving passion behind a marital tragedy - but this time around it's the wife, not the husband, who is the errant partner.
Connie and Edward Sumner (played by Diane Lane and Richard Gere) are a seemingly happily married couple living in suburban affluence with their nine-year-old son Charlie (Sullivan).
Nothing is particularly wrong with their marriage, but when Connie encounters Gallic charmer Paul (Martinez) by chance while shopping in New York's SoHo, she succumbs to the temptation of an affair.
But affairs, as one of Connie's friends remarks, "always end disastrously" - at least they do in Lyne's moralistic universe.
Connie and Paul make love with wild abandon in his artfully disordered apartment, the corridor outside, a restaurant, and a cinema. Unsurprisingly, Edward senses that something is amiss and hires a private detective to follow his wife.
Catastrophic events predictably ensue - but not necessarily the ones you would imagine.
"Unfaithful" is a remake of Claude Chabrol's masterly 1969 thriller "La Femme Infidèle", but whereas the French original was marked by cool restraint, Lyne's direction is typically overheated.
Chabrol never showed us his adulterers together; Lyne pulls out all the stops to display his lovers' erotic trysts.
More worryingly, he misjudges the mood of several key scenes, giving rise to some unintentional comedy. Gere too, though good, doesn't quite carry off all his character's changes of mood.
Lane, however, is tremendous. Whether portraying hesitancy, fear, trembling desire or passionate surrender, she is always honest, truthful, and utterly convincing.