#1 INTERNATIONAL BESTSELLER • A terrifying new thriller in the the internationally bestselling Killer Instinct series: Detective Joona Linna finds himself on a collision course with a terrifying killer whose past is more troubling than anyone could imagine. “One of those rare books that is truly difficult to put down.” —New York Journal of Books A brutal killing spree at a home for wayward teens. One girl is dead, another is missing. Joona Linna scrambles to track her down before the death toll mounts.