Blue Grotto

When a reluctant CIA agent gets dragged into a new assignment, the first thing he realizes is that there are sharks in the water. After all, he explains on arrival, he’s been bitten by one before.
Sent down to the Caribbean to locate a German U-boat lost during the war, he finds he must rely on the help of the local resort staff, and the creatures of the sea.
Unbeknownst to him, another search is also under underway, but they are not looking for a sunken submarine.
They are after sunken Greek treasure... in the lagoon of the same resort that Sam is forced to use as his base of operations.
What neither understands when they arrive, is that both are being watched over by the Goddess of the Sea.
She’s been there for a very long time… and she isn’t interested in sharing.
Beware the little mermaid.