Thousands of adults enter an essay contest ("describe your worst nightmare") for a chance to meet a legendary horror-movie-franchise director (think Wes Craven) and see a rough cut of his latest movie. Each of the winners (all of whom are 18-22, it seems) is brought to the remote B&B (decorated as a replica of the hotel in his movies), where they get to know each other before their Adventure the following day. Their adventure brings them to an abandoned amusement park, where they'll all need to confront their worst nightmares. The winners, the ones who will get to see the rough cut: anyone who survives their ride. 
 This really is more of a horror movie than a book, though it is written in words and printed on paper. We don't see much beyond broad strokes for any of the multiple POV characters, so we don't really care when any of them disappear (and in fact one is conveniently excised from the plot before we even meet her, only to become an inexplicable plot device later). Like teen slasher/horror movies, the plot falls apart if you stare at it hard (view spoiler)[(why would the real director not have put out a notice that he wasn't actually behind the contest, promoted through his mailing list--or announce the names of the real winners, maybe? If the deranged killer from Ivy's nightmares were truly after her, who are the other six people invited on the excursion, and why?) (hide spoiler)]. HOW FORTUITOUS, then, that the sequel comes out this July.