The San Telmo: a Spanish merchant vessel lost in a hurricane off the coast of Archer's Grove while carrying a magnificent dowry home to the Spanish Princess. Chris, Carrie, and Maddison think they know where it is. But if they want to find the ship, they're going to have to survive screaming caves, psychotic oceanography professors, dangerous cave floors, ghosts--and a boat with one terrible paint job. But for Aunt Elsie, who set them on this investigation, they're willing to brave anything.