An overturned coach full of students. A stranded cable car full of strangers. An isolated chalet full of friends. Outside, a snowstorm rages. Inside one group, a killer lurks. But which one? And why is no rescue coming? What are they trying to escape from? And who are the terrifying Whistlers? During a deadly snowstorm, Hannah awakens to carnage, all mangled metal and shattered glass. Evacuated from a secluded boarding school, her coach careered off the road, trapping her with a handful of survivors. Meg awakens to a gentle rocking. She's in a cable car stranded high above snowy mountains, with five strangers and no memory of how they got on board. Carter is gazing out of the window of an isolated ski chalet that he and his companions call home. As their generator begins to waver in the storm, the threat of something lurking in the chalet's depths looms larger. Outside, the storm rages. Inside one group, a killer lurks. But which one? And who will make it out alive?