Nemo and his fellow inmates at Kalpani Penal Colony are the slave labourers building an ironclad submarine - the Nautilus. Once finished, Nemo and a trusted crew plan to escape on it. But when Director Crawley arrives to demand the Nautilus be moved to Bombay to be armed - today - Nemo must leave. Now. With whoever he can muster as crew.

On Karajan the crew meet the eccentric White Rajah, but can they trust his hospitality? Nemo discovers a shocking truth, and Humility and the crew learn who Nemo really is.

Captain Nemo and his starving crew go ashore on a seemingly deserted island in search of food. When Blaster goes missing, Nemo and Humility embark on a daring rescue mission but soon encounter a giant electric eel.

When an eerie red glow appears, the giant eel suddenly releases the Nautilus, it turns out to be a chain of underwater volcanoes. Without steering power, the Nautilus continues to sink towards the dangerous lava - and it soon becomes clear that only Humility can save the crew.

The underwater volcanoes turn out to reveal a clue to the legendary underwater city of Atlantis. A small group goes exploring and finds what appears to be an ancient outpost of the lost civilization, but also realizes that it is home to terrifying sea lilies and the crew must fight for their lives.

A daring battle between the Company ships Dreadnought and Nautilus leaves both stranded in the Arctic ice, leading to an uneasy truce. Nemo reunites with a friend from his past and is shaken by more revelations about his father.

When it is revealed that Nemo has been too daring and put the crew in danger, they lock him in his cabin and Boniface takes command instead. At the magnetic north pole, the problems pile up. Nemo must unite his divided crew by telling them who he really is.

When Nautilus finally arrives at the treasure, they realize that it has not been forgotten at all, on the contrary, it is guarded by wild warriors. Nemo feels that he has led his crew to the end of the world - for nothing.

The Nautilus crew spread rumours that the East India Mercantile Company is failing. When the stock price plunges, a shareholder meeting is called for tonight. Nemo and the crew have three hours to scheme their way into that meeting, so they can dissolve the Company forever.