A therapist uncovers clues to an unsolved murder as a deadly new threat emerges in the New York Times bestselling author''s psychological thriller.

A family of four is murdered in their hotel room. A single mother and her boyfriend are stabbed to death. It''s a sordid history of violent crimes—separated by decades.

Olivia Barker is a therapist with no connection to the murders. But she has heard things. Stories that keep her up at night. Details that only a killer would know. A killer who could be one of her patients . . .

Olivia has no proof for her suspicions. But as the body count rises, so do her fears. A rock is thrown through her window; her car tires are slashed; a chilling message is scrawled on her bathroom mirror. Olivia knows she''s getting closer to the truth. But the truth could be the last thing she''ll ever know . . .