Chase Nelson loves summer vacations on Sanibel Island. This year he's especially psyched because he found an old book with a map pointing the way toward a long lost, buried treasure on the island. He's on a quest to get rich and along the way he meets some interesting characters: Nava, a beautiful mermaid, Lottie, a sassy seagull and Benji, a moody dolphin. Together they search the entire island to find their treasure. What they find, though, is much more than they bargained for.