After the decline in Atlantean culture following the sinking, Kida, now queen and married to Milo, who decided to stay in Atlantis, is using the Heart of
Atlantis to restore the city's former glory. Milo's comrades and Preston Whitmore arrive in Atlantis; while their arrival is unexpected, the Atlanteans welcome their old friends back into the city. Unfortunately, they have come to inform them of a mysterious creature causing trouble on the surface. Kida suspects that the creature might be Atlantean, stirring mixed feelings about her father's decision to keep the crystal hidden. They arrive in
Trondheim,
Norway and discover that the mysterious problem is actually the creature known as the
Kraken, which had been attacking shipping freighters and taking their cargo to a cliffside village. At first they presume it to be an ancient Atlantean war machine, but they discover that the town
magistrate, Edgar Volgud, seems to be controlling the Kraken. They soon learn, though, that the Kraken itself is the master, having made a deal with Volgud to preserve the life of the town and Volgud's lifespan in exchange for their souls. When they blow up the Kraken, Volgud's immortality ceases and he disintegrates, while the spirit of the village is restored. All the while, Kida is learning about the outside world and is adapting well. However, she still feels guilty, as there could still be other Atlantean war machines in the world causing problems. Their next mystery is in the
Southwestern United States, involving coyote spirits. They later find a hidden city in
Arizona that contains Atlantean architecture, which Kida realizes is an abandoned Atlantean colony. A sly shop owner, Ashtin Carnaby, intends to pillage the place for its valuables, but the spirits then turn him into one of them. The wind spirit Chakashi trusts them with the knowledge of their sanctuary and informs Kida that she can choose Atlantis' destiny. Returning home, the adventurers discover that one of Whitmore's old competitors, Erik Hellstrom, who went insane believing he was
Odin, the Norse king of the gods, after a
stock market crash sank his company, broke in at night and stole one of Whitmore's possessions, an ancient spear called the
Gungnir, an artifact of Atlantean origin. When they track him down in the
Nordic Mountains, he presumes Milo to be the god
Loki and Kida to be his long-lost daughter
Brunhild. Then, "Odin" uses the spear to cast Milo, Mole, Vinny and Audrey out of "Asgard" before kidnapping Kida and dressing her in Norse clothing. He explains that his intentions are to end the world in
Ragnarök, the prophesied apocalypse told in Norse mythology. He creates a lava beast and an ice beast to destroy the world, but Vinny distracts the monsters long enough for Kida to retrieve the spear and vanquish the beasts. During these escapades, Kida comes into a greater understanding of just how powerful the crystal is, and that she must choose between hiding it and sharing it with the rest of mankind. Having retrieved the spear, Kida realizes her father was wrong to hide the crystal from mankind. She combines the Spear with the Heart and lifts Atlantis above the water. Whitmore narrates that from then on, the world was a better place. ==Cast==