Grave Descend - Michael Crichton

Leagues below the sparkling blue water of the Caribbean Sea lies the mysterious wreckage of the Grave Descend. Protected by a wall of coral reef and blood-thirsty sharks, the corpse of the sunken yacht has been deemed unrecoverable by every diver in the world. For McGregor, a thirty-nine-year-old diver with a long history of unsavory salvage jobs, it’s his last chance at a big payday.