Cookiecutter sharks: Captain Barnacles and the crew investigate why mysterious holes have started to appear in their equipment -- Lost lemon shark: The underwater explorers go in search of a lemon shark that has hurt its nose and is struggling to find its way home -- Dwarf lantern shark: Captain Barnacles and the team try to find an injured dwarf lantern shark -- Giant jelly: The crew tries to rescue Peso when he becomes trapped inside a giant jelly -- Hungry pilot fish: A lost pilot fish who eats ocean gunk cleans up the crew's dirty gups, while Captain Barnacles tries to work out why a whitetip shark is chasing the gup-a -- Porcupine puffer: Barnacles, Kwazii and Peso venture back inside a whale shark to retrieve a porcupine puffer fish that was accidentally swallowed.