Five women go on a hike. Only four return. Jane Harper, the New York Times bestselling author of The Dry, asks: How well do you really know the people you work with? When five colleagues are forced to go on a corporate retreat in the wilderness, they reluctantly pick up their backpacks and start walking down the muddy path. But one of the women doesn´t come out of the woods. And each of her companions tells a slightly different story about what happened. Federal Police Agent Aaron Falk has a keen interest in the whereabouts of the missing hiker. In an investigation that takes him deep into isolated forest, Falk discovers secrets lurking in the mountains, and a tangled web of personal and professional friendship, suspicion, and betrayal among the hikers. But did that lead to murder?