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Octonauts S3E18 — The Urchin Invasion

8.6

Octonauts•Season 3•Episode 18

The Urchin Invasion

8.6/10 · 11 votesMar 21, 201411 min

Ranked #3 of 20 in Season 3•+0.4 vs season avg

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!

Previous episodeE17 · The Immortal Jellyfish Next episodeE19 · The Hammerhead Sharks

Seasons11

All 1 2 3 4 5 6 7 8 9 10 11

Cast10

Keith Wickham

Keith Wickham

Simon Greenall

Simon Greenall

Jo Wyatt

Jo Wyatt

Rob Rackstraw

Rob Rackstraw

R

Ross Breen

Captain Barnacles

Teresa Gallagher

Teresa Gallagher

Dashi

M

Michael Murphy

Vegimals

Paul Panting

Paul Panting

Peso

Mary Murphy

Mary Murphy

Dashi

Shelley Longworth

Shelley Longworth

Additional Voices

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Episode Summary

"The Urchin Invasion" is episode 18 of Octonauts season 3. It scored 8.6/10 from 11 votes, ranking #3 of 20 episodes this season (season average 8.2). It aired on March 21, 2014.

Next: E19 · The Hammerhead Sharks Best of Season 3