|The Cookiecutter Sharks|
|Season 01, Episode 31|
|Air date||January 20, 2011|
The Giant Jelly
While the Octonauts are in the Gup-A, something attacks them. Tweak soon discovers bite marks on the Gup-A's metal body. The Octonauts then try to find out what's biting their equipment until Shellington finds a row of teeth belonging to the troublemakers. The Octo-cam wasn't working and a blue whale was being tickled(he was being bitten, by fact), so Kwazii, Tweak, Captain Barnacles, and Peso get out a fake whale balloon and surprise the cookiecutter sharks, which show them how they tricked them.
- At the end of the episode when everyone is laughing, their mouths are not moving and their eyes are not closed.