If you hear it, it's too late. "A really entertaining thriller [that] like Michael Crichton . . . keeps racheting up the suspense." -Booklist In the shadow of Mount Hood, sixteen-year-old Tennant is checking rabbit traps with her eight-year-old sister Sophie when the girls are suddenly overcome by a strange vibration rising out of the forest, building in intensity until it sounds like a deafening crescendo of screams. From out of nowhere, their father sweeps them up and drops them through a trapdoor into a storm cellar. But the sound only gets worse . . .