The Phantom Shark! Barby Brant finally gets to leave Spindrift Island and accompany Rick and Scotty on an adventure. The three Spindrifters and Chahda meet their friends the Warners on the trawler Tarpon and head off to map fishing grounds in the exotic South Pacific. They soon run head long into a mystery concerning a mysterious individual called the Phantom Shark, who sells the best pearls to be be found anywhere and has a reputation for being a most dangerous person to cross.