A group of strangers awake in a locked asylum ward with no idea of who they are or how they got there. They are half-naked, cold and frightened, but they are not alone. Who has erased their memories? Why have they been imprisoned? And what is the supernatural force that is slaughtering them one by one? The answers wait deep in the darkness where a beast hungers to feed, escape is virtually impossible, and the shadows of sanity may hide the most shocking revelations of all.