Dive into adventure in the last unknown territory on Earth - the sea. Join Robby Hoenig and a cast of characters as unusual as any ever met on a distant planet . . . In the third Robby Hoenig adventure, Secret Under the Caribbean, the key to a baffling puzzle - and the truth about a mysterious monster - are locked inside a sunken Spanish ship . . . Gordon R. Dickson's Robby Hoenig adventures are timeless young adult stories in the tradition of Arthur C. Clarke's Dolphin Island.