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.

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.