Seventeen-year-old Iris Hollow has always been strange. Something happened to her and her two older sisters when they were children, something they can’t quite remember but that left each of them with an identical half-moon scar at the base of their throats.

Iris has spent most of her teenage years trying to avoid the weirdness that sticks to her like tar. But when her eldest sister, Grey, goes missing under suspicious circumstances, Iris learns just how weird her life can get: horned men start shadowing her, a corpse falls out of her sister’s ceiling, and ugly, impossible memories start to twist their way to the forefront of her mind….