Captain Barnacles Bear, Lieutenant Kwazii Cat, Medic Peso Penguin and the crew head off on an adventure to the deepest, darkest depths of the Amazon River in search of a hidden city full of treasure.

The Octonauts help him move the research base before it falls into an ice chasm, but more trouble is on the way - the chasm lies between a group of Adelie Penguins and their breeding grounds.

When the Octopod goes in for repairs the Octonauts take a vacation, and Peso accompanies Barnacles to help his sister and her new polar cubs learn to navigate the harsh conditions of the frozen arctic ...

The Octonauts return in a special episode of the animated adventure series, which sees Captain Barnacles Bear, Lieutenant Kwazii Cat, and Medic Peso Penguin ready to dive into action whenever ...