"While the Thea Sisters are on a tropical vacation in the Bahamas, they stumble upon an old pirate map. It's related to a local legend. Could it lead to treasure? The five mice venture onto the sparkling Caribbean Sea to follow the map--but someone else is trying to find the treasure first"--Page 4 of cover.

Amy and Dan Cahill hit the high seas as they follow the trail of some infamous ancestors to track down a long lost treasure. However, the real prize isn't hidden in a chest. It's the discovery of the Madrigals' most dangerous secret and, even more shockingly, the true identity of the mysterious man in black.