Intimidated by bullies, Samuel Waters tries to master the art of invisibility. He does his best to go unseen at school, hiding inside his locker to read adventure novels that help him escape. As Samuel reads, he daydreams that one day he will become as brave and courageous as the heroes in his books. He longs to live his own adventures, but he never expects his dreams will come true. Little does Samuel know that his fantasies will become reality during his summer visit to the family lake house with his grandfather, who is his guardian and only relative. There, a mysterious voice contacts Samuel in a nearby forest, summoning him to Pearl Cave. He soon discovers that the cave's many legends are true, while learning something important about himself.