As Castle and Alexis travel to London, their routine flight turns deadly when the plane's Air Marshal is found murdered. With the help of Beckett on the ground, Castle and Alexis race against time to find the killer before he carries out his fateful plan.

Death in the woods draws Castle back to a terrifying and defining event in his childhood. Investigation leads to obsession, as he attempts to unearth answers that have eluded him for decades, all while Beckett faces a crossroads of her own.