Captain Barnacles leads ex-pirate Kwazii, medic Peso and the rest of the Octonauts into thrilling underwater adventures! With help from their fleet of gups, they explore the world's oceans, rescue the creatures who live there and protect their habitats. Join the Octonauts in 6 exciting missions. A lion's mane jellyfish gets its long and stingy tentacles tangled in the bubble engine, unintentionally flooding the Octopod and causing havoc in "The Lion's Mane Jellyfish". Meet Barracudas when Shellington and the Vegimals are on a mission to replant a mangrove forest, and see 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.