The murder victim's fingertips were severed and her body mutilated. Recognizing the need for expert psychological insight on this gruesome case, LAPD homicide detective Milo Sturgis calls in his friend and colleague, psychologist Alex Delaware. Alex is shocked to realize he recognizes the victim - he and his girlfriend, Robin, saw her two nights earlier at a restaurant on its last night of bussiness. Even more shocking - the time of death suggests the beautiful and melancholy young woman alone at the bar perished not long after Alex and Robin noticied her sitting there. When a lead offers up the victim's nickname - Mystery - the case takes an alarming turn.