After Capt. Nemo introduces himself to the group, the island dwellers are invited to the hidden grotto where the Nautilus lies anchored. The interior scenes of the Nautilus exhibit great set design and tremendous attention to artistic detail. In this scene aboard the mysterious craft Capt. Nemo wears a green velvet jacket and an elegant white shirt while he pours drinks for everyone and discusses his vision for world peace. Wax candles add a bit of ivory splendor to the overall burgundy and gold color scheme, and the wide portholes exhibit circular windows of ethereal blue looking out toward the rugged walls of the grotto. Nemo states unequivocally, "What I did was in the name of peace," in an attempt to justify his method of destroying warships and navies across the oceans of the world. Capt. Harding disagrees that these actions were justified, and there is some tension as the group listens to Nemo broaden the foundation of his philosophy, tactics and mission. Nemo relates that he has been engaging in "experiments in horticultural physics" in an attempt to gain "an inexhaustible food supply." He wants "to conquer famine and economic competition," in a quest to destroy the causes of war. Nemo further explains that he set the explosive charge which sent the pirate ship to the bottom off the coast of the island. He plans to re-float the ship by patching the damaged hull and pumping air into the submerged vessel. He asks Capt. Harding if he's "ready to dance with the devil" by providing the manpower to re-float the ship. The group begins to understand Nemo's scheme and agrees to provide the intense labor needed to complete the project.
Racing Against Time & an Active Volcano
The island dwellers cut bamboo to make a pipeline for Nemo's salvage plans, using the liquid from rubber trees to act as sealant for patching material. It is a laborious process but the team seems to be making good progress just as some spectacular volcanic explosions take place on the island. One scene features a "weird sunken citadel" which looks like the City of Atlantis, viewed by the divers as they approach the sunken pirate ship. Another scene features a battle with a giant sea creature known as a "Cephalopod" or "Chambered Nautiloid," subdued only when zapped by Nemo's fantastic underwater electric gun. When the volcanic explosions take place and seem to accelerate in ferocity, Nemo announces that their time is up and the island is doomed. In a depressed state, the island dwellers take shelter in the relative safety of the cabin of the Nautilus, but Lady Mary bluntly implores the group, "Is this the infinitely resourceful genius you told me about?" Nemo glumly responds, "Nothing can be done," preferring only to play the pipe organ and wait for the inevitable end. When the group turns to Capt. Harding for a glimmer of hope to escape their present predicament, Nemo despondently replies that Capt. Harding is "a man of faith, not of reason." Just then Capt. Harding describes a possible method of re-floating the sunken pirate vessel by repairing the damaged balloon fabric, then inserting the deflated balloon into the cargo holds of the ship and pumping air into the fabric, re-floating the ship. It is a brilliant idea and Nemo responds, "By heaven, it is a chance!"
Flowing Lava and the Final Cataclysm
As the pumping operation to re-float the sunken pirate ship begins, flowing lava descends from the active crater of the volcano, destroying everything in its path. Falling rocks pepper the exterior of the Nautilus, even as magnificent light and colors illuminate the hidden grotto and its doomed submarine. A cataclysmic avalanche takes place on the island, with rocks tumbling down the mountainside as trees and topographical features disappear beneath the burning lava. The survivors are successful in their quest to re-float the pirate ship, suddenly witnessing the final fury of volcanic activity as they look toward the spectacular explosions on the island. Neb says that it "looks terrifying," just as the group celebrates their timely deliverance from catastrophic destruction. The survivors mourn the loss of Capt. Nemo who is caught in the grotto amidst the final avalanche and suffers an accidental death aboard the Nautilus. The underwater city collapses off the shore of the island, leaving only rubble in place of what once was a remarkable civilization. As the group sails away on their resurrected sailing ship, Capt. Harding narrates the final words of the film in his voice-over, relating that the survivors "pledged to work for a peaceful and bountiful world," ever mindful of the imagination, work and sacrifice of Capt. Nemo.