After landing the foster family of her dreams, fourteen-year-old Nell Parrish looks forward to spending their first weekend together at their lakeside cabin. The promise of a new start. A new life. A better life. But nothing will prepare Nell for the nightmare that awaits them there, or the many haunting revelations following fast on its heels. Everything Nell thinks she knows—about our world, our reality, and herself—is wrong, and one night of unspeakable terror will prove it. In the dead of night, a killer carves a trail of bloodshed across the quiet mountain landscape. Merciless. Unstoppable. Supernatural. Every victim is left in a similar state: on their knees, their flesh in tatters, with expressions of rapture upon their dying faces. Whatever is doing this, it's clearly not of this world, and only something—or someone—equally otherworldly can possibly stop it. Whatever—or whomever—that may be, they’d better hurry. Because Nell is running out of time.