Disney Atlantis: The Lost Empire
Thousands of years later, Milo Thatch is an aspiring, kindhearted, and dreaming linguist and explorer, although his employers, the staff of Smithsonian Institution, has little use for him other than keeping the boilers running. He believes that his research has revealed the location of The Shepherd's Journal, a Viking manuscript that allegedly reveals the way to Atlantis. His dreams are to prove to the world, that his grandfather, Thaddeus Thatch, really did discover a clue that could lead to the discovery of one of the greatest mysteries of all. After his proposal is rejected, a mysterious woman named Helga invites him to see her employer. Helga takes him to Preston B. Whitmore, an eccentric millionaire who, owing a debt to Milo's grandfather, has funded a successful effort to find the journal. Now that it is in hand, Whitmore recruits Milo to interpret the book and lead an expedition to Atlantis.
Milo sets out with a crew headed up by Rourke, a military man who led the expedition to recover the journal, Helga, and a crew of oddballs. Among the crew are Vinnie, the crew's demoman, Mole, the geology specialist, Dr. Joshua Sweet, the ship's medical officer, Audrey, the tomboyish mechanic, and Cookie, the ship's western redneck cook. They set out in a submarine, the Ulysses. As they approach Atlantis, the Ulysses is attacked and destroyed by the Leviathan, a huge robotic defender of Atlantis. Milo, Rourke, and crew escape in small sub-pods and a cargo hauler and, reaching an underground cavern described in the book, continue ahead on foot and vehicle. They are tracked all the while by some Atlanteans.
Reaching Atlantis, they are greeted by Kida, now a young woman, although "young" is relative to her appearance only, as she is now many thousands of years old. She brings the group to meet her aging father, who wants them to leave as soon as they are able, since their presence cannot mean any good. Atlantis has fallen into ruins since disappearing into the earth, and Kida enlists Milo's help deciphering the runes throughout the city, the Atlantean written language having been unknown to the people for centuries. He helps her discover the nature of the heart of Atlantis, but can't tell how it works, since a page of the journal is missing.
Rourke turns out to have the missing page and manages to betray Milo. He and Helga having known about the Heart all the while, and he turns the tables by forcing Milo and Kida to help him find the Heart of Atlantis so that he can take it back to the surface and make a fortune from its sale. Once found, it merges with Kida, causing her to fall into a trance as her body becomes a glowing blue crystal. Rourke locks up Kida and prepares to leave for the caves and capture the crystal. Before that, he punches Milo, and mocks him, breaking his beloved grandfather's picture, and tears of sorrow, heartbreak, and despair well up in Milo's eyes. But just before they leave, his friends have a dramatic change of heart, and go back to help Milo up. Rourke leaves, and prevents the crew from following him by blowing up the bridge with one of Vinnie's explosives. Later, in the palace, the King explains to Milo all about the Heart of Atlantis, on why the crystal had a mind of itself, and why Atlantis went underwater. Before his death, he gives his crystal to Milo and tells him to save Atlantis and Kida. Milo is reluctant as first, pointing out that every bad thing on this mission happened because of him. But with courage and support from Sweet, Milo rallies the crew and the Atlanteans to stop Rourke, and manages to restart several Atlantian vehicles to create an aerial fighting force to challenge the villains.
In the ensuing battle, Rourke is destroyed, Helga is killed, and Kida is liberated, but a volcanic eruption ensues. The city's total destruction is imminent until Milo and Kida are able to restore the city's systems to full power which include restarting the sentinels who rise to protect Atlantis. The Atlanteans thank the visitors who helped save Atlantis and give them a huge treasure. The surviving crew, now insanely wealthy, return to Whitmore's mansion to get their stories straight and cover up the existence of Atlantis, while Milo stays to help Kida rebuild the Atlantean empire.