A teenager, whose sister went missing in the desert and came back different, is determined to rid her sibling of whatever dark entity she is sure has possessed her, in this haunting speculative thriller about sisters and the bonds that keep them close.

Theres something wrong with Milas sister. Ever since Liv went missing during a camping trip in the desert, shes been . . . different. The doctors say shes fine, but Mila isnt so sure.

She and Liv used to be so alike: same height, same unremarkable looks, same bookish tendencies. But now, Livs brown hair is threaded with gold and her gray eyes look green in the light. Stranger still, Liv is popular, not just at school but online, where she regales hundreds of thousands of strangers with the mysterious story of her lost night.

Everyone is eating out of Livs hand. Everyone, that is, except Mila. Shes the only one who sees the truth: The Liv who went to the desert isnt the same girl who came back.

The only way to prove it is to uncover what really happened that nightand not just to Liv. Because Mila has her own secret: The same night Liv went missing, Mila faced a monster. And the longer she spends in the dark, the closer she comes to facing it again.