What started out as a four-day sailing adventure off the western coast of Australia for ten-year-old Matt Sawyer and his older brother, Sam, turned into an epic battle for survival that no one could have predicted. Out of nowhere, a freak storm took them by surprise on their third evening at sea. It blew them off course, disabled all the navigation and communication instruments, and landed them on a hostile, uninhabited island. While scouting the island for desperately needed water, Matt and Sam stumbled across unusual tracks in the sand. What type of creature had made them? They would soon find out when Sam is brutally attacked by an animal that had no business being there and Matt is suddenly in charge of his older brother's survival and planning their escape from the island. Every day is a struggle for water, food, and shelter as they try to stay two steps ahead of the beast that is intent on finishing the job. The cave they have taken refuge in has a mysterious past, but will it help or hinder the brothers? After a harrowing escape, Matt and Sam think their ordeal is over when they return home. But the island isn't through with them yet-- it is looking to reclaim one of its own.