It was supposed to be the perfect vacation, dreamed up by Kate as the ideal way to turn 40: four best friends and their husbands and children, spending a week in a luxurious villa under the blazing sunshine of Provence. But there is trouble in paradise. Kate suspects that her husband is having an affair and that the other woman is one of her best friends. One of these women is willing to sacrifice years of friendship and destroy her family. But which one? As Kate closes in on the truth in the stifling Mediterranean heat, she realizes, too late, that the stakes are far higher than she ever imagined. And someone in the villa may be prepared to kill to keep their lies hidden.