The mission to explore Antarctica becomes a desperate rescue as a group of sea stars and urchins is threatened by a rare underwater icicle that can freeze creatures on the seabed.
The Octonauts must help a giant sunfish who can't swim straight, before it hurts other sea creatures and itself.
Captain Barnacles runs into a long-lost friend (an arctic fox named Professor Natquik) in Antarctica, where they must work together to prevent a group of penguins from falling into an ice chasm.
Examining a sick sea sponge, Peso is surprised to discover that all sorts of creatures live inside it, treating it like a hotel, a behaviour known as commensalism.
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.
Kwazii is spooked when he spots what looks like a giant underwater spider! But it turns out to be a very old Spider Crab who needs the Octonauts' help!
When the Octopod's waterworks are flooded with frightened Humuhumu fish, the Octonauts have to find a way to flush them out!
The Octonauts have their hands full as they look after a headstrong young Lemon Shark who's hurt his nose and can't find his way home.
The Octonauts are on a mission to recover Captain Barnacle's lost Octo-compass, but it's been taken by a crafty, shape-shifting Cuttlefish!
Kwazii covets the treasure in a sunken pirate ship - but it's protected by slime-squirting Slime Eels.
When Captain Barnacles and Peso get lost in the icy Arctic sea, a pod of Orcas help the Octonauts find them.
The Octonauts try to pull Peso out of an oceanic trench and get some help from a strange-looking creature with a see-through head - a Spookfish.
A timid sperm whale must conquer his fears and dive deep down to help the Octonauts release Peso from a giant clam.
When a young dolphin follows Kwazii home, he has to babysit while the other Octonauts search for its mother.
When Shellington gets trapped in the middle of a massive Jellyfish bloom, it's up to the Octonauts to rescue him.
When Kwazii and Peso are shipwrecked on a desert island, they encounter a Combtooth Blenny - a fish who walks on land. They enlist him to send an SOS message to the other Octonauts.
Dashi snaps a picture of what appears to be a sea serpent, but the truth is stranger than fiction when it turns out to be an awesomely long oarfish.
What keeps making strange holes in the Octonauts' equipment? Turns out it's a trio of pesky Cookiecutter Sharks, the mosquitoes of the sea.
This feature is only available for subscribers. Please contact your EnhanceTV school administrator or email firstname.lastname@example.org