Clever Jake, his brave and curious little brother Max, and their dad were ready for a fun vacation-they didn't know that the little Greek town of Katakolon had secrets hidden in its morning fog. On the morning the family arrived, Jake and Max met the mysterious lighthouse keeper who told them the story of a sea monster he believed had lived off the coast of Katakolon. Curious about his story, they thought it would be fun to take their dad out to fish using the lighthouse keeper's boat which also would give them opportunity to explore his story.

But the lighthouse keeper's story wasn't just tourist bait. When the Greek coast vanishes behind them, Jake and Max are drawn into a magical mystery that stretches back thousands of years-all the way into the time of myth and fairy tales.

With only a mysterious blue stone to guide them, Jake and Max will have to find their way back to safety and escape the grasp of an ancient monster.... Who are the lighthouse keeper and his son, and what happened to them?