17 yr. old Moses LeConte sees a postcard from his uncle, Augustus LeConte with his grandmother’s address only and no message on the card. It is from Havana, Cuba and shows the old fort at the Havana harbor, Ft Morro, now a prison in Havana. Moses deduced his uncle was stuck in Havana for some reason and in prison. He decided to sail to Havana on his sailboat and find out what happened. He enlists the aid of his two friends, Jack Barker and Charlotte Pace to go with him. They are all out of school and it will be an adventure. Along the way, they encounter drug smugglers, prison guards, a stolen emerald and while skin diving they battle a 10 foot boa constrictor in the clear waters of Cuba. It is a real teen’s adventure.