After getting away with murder, Grant Tavish plans his own form of justice, but before he can act upon it a cave system collapse traps him and four other teenagers miles below the surface, where they soon discover that they aren't alone. Involved in a fatal accident, Grant Tavish is willing to face the consequences. But being a senator's son means getting away with murder-- despite the headlines of "affluenza". During a cave excursion on the Appalachian trail Grant seizes the opportunity to take justice into his own hands by staging an accident and never coming back. When the cave system really collapses, he's trapped miles beneath the surface with four other teens from much less fortunate circumstances. As they struggle to survive, they share their innermost secrets and fears. Soon they realize there's something else down there. And it's hunting them ... -- adapted from jacket.