For Simon, the trip was supposed to be a once in a lifetime gift: a journey to the Amazon River Basin, the land that he had dreamed about visiting since he was a child. His enthusiasm for the trip may be tempered by the poor conditions of the boat and their captain leading the tour, but most of the tourists think they can look the other way on it. Except things go wrong quickly. After a horrific accident, Simon and the other tourists find themselves trapped on a tiny island in the middle of the river. It's the rainy season, and the river is rising. The island is surrounded by hungry bull sharks that won't let them swim away. And worst of all, the sharks might not be the only blood-thirsty killers among them. It was supposed to be the trip of a lifetime. Instead, they'll be lucky if they make it out with their lives at all.