No Exit: A Tense Locked Room Suspense Novel and Inspiration for the Film

College student Darby Thorne is traveling to Utah to visit her dying mother when she becomes trapped by a severe blizzard in the Colorado mountains. Unable to continue driving, she takes shelter at a remote highway rest stop with four strangers. While attempting to find a cell signal outside, she discovers a little girl locked in an animal crate in a van parked nearby. With no cell reception, no telephone, and no way to leave, Darby faces an impossible situation. She must determine which of her fellow travelers is the kidnapper, find a way to free the child from the van, and escape safely. As the situation grows increasingly dangerous, Darby must decide who she can trust while racing to save both the girl's life and her own.