After her mom skips town, sixteen-year-old Morgan is eager for a fresh start. What she gets instead is a crumbling house at the edge of the woods, a lonely town, and a weird blue door in the basement that opens into nothing at all.

While her dad and older sister settle into Wolf Creek with ease, Morgan isn't so lucky. Even aside from the bullying at school and the family upheaval, something else is stirring at the edge of her world. Her fascination with the blue door spirals into an obsession. Unseen figures watch from the trees of a wild forest that shouldn't exist. The boundary between reality and something far older begins to thin. Through it all, Morgan has made a promise: I will protect the door. And what she faces are forces that feed on fear, grief, and isolation.

But the greatest threat of all lies beyond the threshold of a place where the rules of her world no longer apply.