A group of friends investigates the mystery of a strange staircase in the woods in this mesmerizing horror novel from the New York Times bestselling author of The Book of Accidents. "Chuck Wendig weaves his magic once more, turning a lonely staircase in the woods into a searing, propulsive, dread-filled exploration of the horrors of knowing and being known."-Kiersten White, author of Hide and Lucy Undying Five high school friends are bonded by an oath to protect one another no matter what. Then, on a camping trip in the middle of the forest, they find something extraordinary: a mysterious staircase to nowhere. One friend walks up-and never comes back down. Then the staircase disappears. Twenty years later, the staircase has reappeared. Now the group returns to find the lost boy-and what lies beyond the staircase in the woods. . . .