Joey (Leighton Meester) fears there could be trouble ahead after her brother Gray (Taran Killam) invites Trevor (Adam Brody), a childhood friend with a troubled past, on their whitewater rafting adventure with two tourists. Once they become stranded in raging rapids, the thrill-seeking trip quickly turns from exciting to utterly terrifying as the rafters are trapped in a desperate fight for their lives, all while someone seems intent on sabotage to ensure shocking secrets stay buried. To survive the wild river, Joey will have to face her fears, and everyone will have to develop killer instincts before they're torn apart by deception aboard the raft, or by deadly waters wreaking havoc all around them.