Two female friends, Karen (34) and Isabel (32) – both attractive, successful and happily married – use each other as alibi for their mutual extramarital relationships. They are always very precise in their cover up stories, including specific details, so they never contradict each other.
Karen gets into trouble when Isabel is murdered at a time when they were supposed to be together. Successively she suspects Isabel’s lover, Isabel’s husband, one of her own temporary lovers and finally her own husband, when it turns out he knew about their deception all this time.
To find out who the perpetrator is, Karen will have to unravel all their previous lies one by one.