Episode 1
The Octopod is attacked by a colossal squid, who drags the ship down an abyssal trench, forcing Barnacles and Kwazii to make a perilous swim outside to confront the gigantic beast.
Episode 2
While Kwazii and Peso have their hands full babysitting a bunch of Adelie penguin chicks, Captain Barnacles must rescue the chicks' parents from a perilous sea storm!
Episode 3
Kwazii finds a mysterious, unbreakable coconut, so the Octonauts seek out the help of some large, island-dwelling coconut crabs to open it.
Episode 4
Peso must perform an emergency fin bandage on a hungry great white shark, but first they need to subdue the giant predator using a trick called 'tonic immobility'.
Episode 5
It's Sea Snakes on an Octopod when a poisonous sea krait lays her eggs in the garden pod, just as Captain Barnacles has to navigate the ship past a treacherous whirlpool.
Episode 6
When the Octonauts are unable to rescue a group of Narwhals trapped behind arctic ice, they recruit a Bowhead Whale to help them break through!
Episode 7
A mouth-brooding jawfish father has lost his eggs, and the Octonauts must brave strong currents and other obstacles to help get them back to him!
Episode 8
Barnacles, Kwazii and Peso venture back inside a whale shark to retrieve a Porcupine Puffer Fish that was accidentally swallowed.
Episode 9
The Octonauts help a group of algae-eating fish stand up to some aggressive damselfish, who are harming their own reef by over-farming it with algae.
Episode 10
A timid sperm whale must help the Octonauts release Peso from a giant clam.
Episode 11
Peso and Kwazii venture down to the midnight zone to help a hurt creature, but what they find is a shipwreck 'haunted' by a spooky-looking long-armed squid.
Episode 12
The Octonauts help clean up a beach after a storm, but things get complicated when the resident fiddler crabs hijack the Gup-D!
Episode 13
The Octonauts help a young manta ray find the secret manta ray feeding grounds, but when they finally locate it, the Octonauts become caught in the middle of a dangerous feeding frenzy!
Episode 14
The octonauts discover a rare showing of a full moon as Kwazii discovers that its known as the Pirate Moon as Kwazii and The Octonauts search for a ship that belonged to the pirate king as Kwazii searches for the sword of the Pirate King until a trio of swordfish prevent Kwazii from getting closer to the wrecked ship.
Episode 15
The Octonauts' floating temperature sensors alert them to a risk of waterspouts due to a rise in sea surface temperature so they decide to retrieve the devices for safe-keeping. But Kwazii gets into an argument with a possessive triggerfish which has adopted one of the devices as its home, and they both get carried away by a waterspout. Kwazii ends up having to defend the fish from a seabird and a swordfish that want to eat it. Luckily the characteristic grunting sounds that triggerfish make when distressed enables the other Octonauts to locate them.
Episode 16
The Octonauts recruit a shape-shifting mimic octopus to help them recover an important vial of medicinal algae from a moray eel's lair.
Episode 17
The Octonauts get more than they bargained for when they use the Octopod to transport a pair of invasive lionfish back to their native habitat.
Episode 18
When two young leafy sea dragons are accidentally separated from their father and brought onboard the Octopod, the Octonauts must find them before they end up in Kwazii's stew!
Episode 19
Running out of air, Barnacles struggles to free his paw from the mouth of a giant clam, while simultaneously directing his crew in a delicate manatee rescue operation.
Episode 20
When a gigantic saltwater crocodile wanders into freezing waters, the Octonauts must figure out how to get the predator back to his warm water home - without anyone getting hurt.
Episode 21
The Octonauts use magnets to try to stop a meteor that's heading toward the Octopod and get an assist from a rock-chomping humphead parrotfish and her friends.
Episode 22
When hungry gulper eels as well as undersea tremors threaten Inkling and Kwazii, Dashi uses the new, multi-purpose Octo Max Suit to rescue them.
