"School's out and Trot and Cap'n Bill are looking forward to a carefree summer of surfing. But trouble surfaces when Grandpa hooks a message in a bottle while fishing. Clia, the Sea Siren princess, and Anko, King of the Sea Serpents, need their help: Merla, their Sea Siren friend, has been kidnapped! Trot, her cat, and her grandfather join the rescue effort which takes them to an old abandoned amusement park island resort, where plans are afoot for...