Saltwater crocodile: A giant saltwater crocodile wanders into freezing waters so the Octonauts try to return the predator to its warm water home -- Decorator crab: When important objects go missing from their ship, the Octonauts stake out the thief who turns out to be a decorator crab, stealing their things to decorate his shell -- Giant spider crab: Kwazii is frightened when he spots a giant underwater spider, but it turns out to be a very old spider crab who needs the Octonauts' help -- Hermit crab: Peso and Tweak try to remove a stuck hermit crab from its shell when the crew are unable to return to the base -- Slime eels: The explorers want to find treasure hidden in a sunken pirate ship, but discover it is guarded by slime eels -- Snapping shrimp: The underwater explorers encounter a snapping shrimp, a small creature that uses its claws to make a loud noise -- Enemy anemones: As two groups of anemones feud with each other, the Octonauts and a group of crabs find themselves caught in the middle -- Fiddler crabs: The Gup-D is hijacked by fiddler crabs when the Octonauts help clean up a beach following a storm.