When the shadows in the ocean go missing, the Octonauts, a team of eight animal underwater explorers, must travel to the Sea of Shade to find them.

When the Octonauts, a team of eight animals that explores the ocean, help a lonely monster, everyone learns the value of friendship and individuality.

Great penguin race: The Octonauts cheer Peso on as he goes home to compete against an awesomely athletic penguin -- Great Arctic adventures: Peso goes with Barnacles to help his sister and her new polar cubs learn to navigate the harsh conditions of the frozen arctic -- Humpback whale: A humpback whale helps Kwazii track down a treasure chest key.

As they travel through deep, dark waters, the Octonauts find themselves in a battle with a colossal squid over the Octopod! Can the crew win this bout of tentacle wrestling? Octonauts, let's do this!