Kelp's only goal in life seems to be to get some 'lucky mermaid' to play Spin-the-Conch, but unfortunately has had no success in his venture. Pearl, his younger sister, tells him, as future king of the ocean realm, he must forego his desire and make something of himself, or forfeit the kingship. When these mer-teens, see an old enemy at the sunken treasure ship, they know the kingdom is in trouble. Can they save the royal treasure, and will Kelp ever...