Episode 1
When Kwazii's Gup-B breaks down in a storm, not even brave Captain Barnacles can save him alone. Fortunately, a chain of reef lobsters lends a hand - and some claws.
Episode 2
Episode 3
The crew pursues crustaceans who’ve hijacked the Octopod.
Episode 4
When Peso's precious medical kit is taken, Barnacles and Kwazii sneak into a dangerous walrus colony to get it back, disguised as a walrus.
Episode 5
When a school of flying fish accidentally make off with a rare book belonging to Professor Inkling, the Octonauts rig up the Gup B to fly after them and get it back.
Episode 6
The Octonauts roam the oceans in search of adventure and fun. Whether it's a perilous voyage to the bottom of the sea or the piratey pursuit of a giant squid, the Octonauts leap into action and always prove that eight heads are better than one! The Octonauts set out to find and photograph Inkling's long lost cousin, the elusive Giant Squid.
Episode 7
When a huge Orca whale becomes stranded on a beach, Captain Barnacles Bear and the Octonauts devise a plan to pull him back into the water, with some help from a group of tunnelling Fiddler Crabs.
Episode 8
Captain Barnacles and his crew must catch a runaway Octopod, when it is hijacked by a group of crustaceans trying to escape their algae-infested waters.
Episode 9
When Shellington gets lost in a dark sea cave, he gets unexpected assistance from some blind Remipedes.
Episode 10
When all the Gups go out of control, Barnacles and Kwazii leap onto the backs of some speedy Sailfish to round them up.
Episode 11
The Octonauts must evacuate sea creatures before an underwater volcano erupts, but there's one creature that won't budge: a slow moving, gelatinous Blobfish.
Episode 12
The Octonauts follow an old map to what Kwazii believes is treasure guarded by a sea monster but, instead, they meet a playful Octopus with all kinds of surprising abilities.
Episode 13
When the Octonauts find an unusual Sea Star on the beach, they search the ocean from top to bottom (literally) to help find its home.
Episode 14
The Octonauts help out an Albino Humpback Whale with a nasty sunburn.
Episode 15
When Kwazii's favorite sub, the Gup B, goes missing, the Octonauts journey into a mysterious kelp forest to find it, meeting strange and interesting creatures along the way.
Episode 16
The Octonauts land on an island for a picnic but must first help some crabs trapped between two warring groups of aggregate anemones. Meanwhile back on the Octopod, a horde of out of control puddings are attacking. Peso wins the contest between 2 types of blobs.
Episode 17
While exploring the Arctic, the Octopod gets trapped in the ice. Only Barnacles's skillful navigation, and the help of a friendly Narwhal, can get them free.
Episode 18
While exploring the deepest part of the ocean, the Midnight Zone, the Octonauts discover a strange rock that happens to be home to a new species of worm.
Episode 19
The Octonauts encounter a snapping shrimp – a small creature that uses its claws to make a big, and stunning, noise.
Episode 20
After an underwater tremor, an injured sea cucumber named Slippy gets loose on the Octopod, so to let her breathe, they flood the ship!
Episode 21
The Octonauts race against time to rescue Tweak's pal, a leatherback sea turtle who's caught in a fast-moving ocean current that's sucking it into a whirlpool.
Episode 22
When Captain Barnacles Bear and most of the crew are unable to return to base, it's up to Peso and Tweak to remove a stuck hermit crab from its shell.
Episode 23
When the Octonauts clean and repair their ship, the Octopod, the resulting noise causes a nearby blue whale to act in strange and dangerous ways.
Episode 24
When Peso's little brother, Pinto, comes to visit, he's more interested in being a pirate than a medic – at least until he accompanies Peso on a mission to rescue Dashi and Shellington in a kelp forest.
Episode 25
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.
Episode 26
The Octonauts lead a pod of Beluga Whales stuck under the pack ice to safety by getting them to follow Peso while he's playing the same tune as the Beluga's song on his xylophone.
Episode 27
The Octonauts are chased by a whitetip shark only to discover all it really needed was a pilot fish to clean its teeth, and it just so happens that they have just met a lonely pilot fish that is hungry for action.
Episode 28
Peso must gather all his courage when he travels deep down to the very bottom of the ocean, the Midnight Zone, and encounters the mysterious Vampire Squid.
Episode 29
After a storm, the Octonauts help a female seahorse search for her missing mate. She tells them, to Kwazii's surprise, that the missing male seahorse is about to give birth to baby seahorses!
Episode 30
The Octonauts must rescue Peso when he gets trapped inside a giant ctenophore.
Episode 31
Some mysterious holes that keep appearing in the Octonauts' equipment turn out to be the work of cookiecutter sharks whose bioluminescence initially made them invisible against the light coming down from the sea surface.
Episode 32
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.
Episode 33
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.
Episode 34
When Shellington gets trapped in the middle of a massive Jellyfish bloom, it's up to the Octonauts to rescue him.
Episode 35
When a young dolphin follows Kwazii home, he has to babysit while the other Octonauts search for its mother.
Episode 36
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.
Episode 37
When Captain Barnacles and Peso get lost in the icy Arctic sea, a pod of Orcas help the Octonauts find them.
Episode 38
Kwazii covets the treasure in a sunken pirate ship, but its protected by slime squirting Slime Eels.
Episode 39
When Peso and the Octonauts aid an enormous Elephant Seal, he overstays his welcome in the Octopod.
Episode 40
The Octonauts must work together as a team to help a lost sardine find her school.
Episode 41
When the Octonauts all pitch in to help save a sick coral reef, they get some unexpected help from a pod of playful dolphins.
Episode 42
The Octonauts travel up a treacherous river to help a young migrating eel on her difficult journey.
Episode 43
The team are preparing for a feast of red seaweed on the Galapagos Islands but a trio of salt-sneezing marine iguanas raid the Octopod and eat it all!
Episode 44
Down in the darkness of the ocean deep, Peso and the Octonauts must help a tiny, injured Dwarf Lantern Shark.
Episode 45
When the Octonauts go on a pirate treasure hunt, Kwazii meets a Parrotfish.
Episode 46
Some electric torpedo rays give the Octopod a jump-start when its batteries go flat during a trip to see Tweak's pal, Sandy the leatherback sea turtle.
Episode 47
Captain Barnacles allows Tunip to use his Octo-compass. But when Tunip loses it, a cuttlefish takes it.
Episode 48
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.
Episode 49
When the Octopod's waterworks are flooded with frightened Humuhumu fish, the Octonauts have to find a way to flush them out.
Episode 50
The octonauts help a 100 year old spider crab which has got its leg trapped in a giant clam whilst en route to its own 100th birthday party. It turns out that Kwazii's afraid of spiders, but he still helps, even though he thought it was a real spider at first.