Octonauts
The Urchin Invasion (3x18)
Season finale
Air date: Mar 21, 2014
The Octonauts head to the kelp forest to visit Shellington's sister, Pearl, and her newborn son Periwinkle - only to find the forest endangered by an infestation of kelp-eating urchins!
- Premiered: Oct 2010
- Episodes: 126
- Followers: 10
- Running
- CBeebies
- Daily at 20
