Bellamy’s man abroad Kneedling has set Fogg and his companions adrift on a lifeboat somewhere in the Pacific Ocean at night in a churning sea. The boat is wrecked in the storm, sending Fogg and Fix onto a beach with a single flask of water. Finding Passepartout’s jacket but not the Frenchman himself, Fix begins to cry—until Passepartout’s voice is heard, and he washes ashore clinging to a piece of driftwood.
Fogg decides to follow the beach until they reach signs of civilization. As they walk, Fix fondly recalls moments with Passepartout—she’s beginning to recognize her feelings for him. Eventually they encounter footprints, to Fix and Passepartout’s delight. But Fogg is defeated. He has realized that the sun has continually moved positions: they’re on an island, and those are their footprints. They may not have circumnavigated the globe in 80 days, but they have rounded an island in less than one.
Passepartout goes to search for water and Fix for food while Fogg halfheartedly attempts to build a shelter. Passepartout discovers a spring, and Fix finds durian fruit, notorious for its odor—not that any of the party know what it is. She saw birds eating it, so it’s presumably not poisonous, but they all can barely choke it down.
As the party sits in Fogg’s leaky shelter that night, Fogg apologizes to them—it’s his fault they’ve ended up marooned, given his journey. They don’t blame him, but reluctantly forgive him at his behest.
The next day, Fix tells Passepartout she’s worried that Fogg is descending into melancholy, just like her mother did, and that he will give up and die on the island. Passepartout goes to speak to him.
He tells Fogg that it is Kneedling’s fault they are on the island, not Fogg’s. And he explains that Kneedling has been trying to delay them for weeks. After apologizing for not telling Fogg about Kneedling earlier, Passepartout also reveals that he was offered—and took, before returning—a bribe by Kneedling, and that he drugged Fogg.
Fogg is furious—even more so once Fix accidentally reveals that Passepartout is behind the thievery of a jewel in Hong Kong that sent Fogg to jail. Fogg orders Passepartout to leave him and Fix, and sets about constructing a raft with which to escape the island.
As he and Fix collect wood, she tries to defend Passepartout. He, meanwhile, catches lobsters then tries to apologize to Fogg. But Fogg sees only a thief and a liar, even after Passepartout explains that he took the bribe because he saw Fogg’s journey as a rich gentleman’s folly but now understands that it means much more to him. Fogg draws a line in the sand to keep Passepartout away. The Frenchman refuses to leave; his friendship with Fogg and Fix is too important, and he will fight for it. When he cooks his lobster, Fix defects to eat some before returning to Fogg.
Passepartout wonders aloud in Fogg’s hearing whom Kneedling was working for, mentioning Bellamy as the only person who would profit from the failure of Fogg’s journey. Fogg defends his old friend, even though Bellamy always belittled him.
Back in London, Bellamy has received a telegram from Kneedling that his wager is won. He’s also present when Fortescue hears that Fogg and Fix have gone missing at sea and are believed dead. Fortescue pens an editorial praising them while the Reform Club organizes a commemoration of Fogg, at which they ask a guilty-feeling Bellamy to speak.
Passepartout works through the rainy night to finish Fogg’s raft, using vines to lash it together. Fogg and Fix find it the next morning and begin gathering food and water for their journey away from the island. Fix finds Passepartout shivering and ill and brings him to Fogg. He orders her to hold him close to keep him warm while he rubs his limbs. They eventually burn their shelter to keep the fire going, then break down the raft for more fuel as the sun goes down.
Passepartout wakes up warmer and better in front of a meager fire the next morning. He thanks Fogg for burning the raft—a decision Fogg says was easy—and says he won’t forget it. Fogg tells him he is right about Bellamy, but also says that his friend probably didn’t want to maroon them; Kneedling was just overzealous. He admits that Bellamy also stymied a similar trip that Fogg had planned in his youth. Fogg was to marry his beloved, Estella, in Paris, then travel the world. But he internalized Bellamy’s doubts and needling and lied to Estella early in the trip, saying that he had forgotten luggage and must turn back. He never saw her again.
Abandoning Estella is the most shameful thing he has ever done, and he deeply regrets it. He had never felt as close a bond with another person after her—until he undertook this journey with Fix and Passepartout.
Fix and Passepartout go on a walk together and are more open about their feelings. Fix didn’t trust Passepartout when she first met him, and now look at everything he has done for her and Fogg. They nearly kiss—but are interrupted by yells from Fogg. There’s a boat on the horizon.
It turns towards them and sends a rowboat. The crew noticed the smoke from Fogg and Fix’s fire and came to investigate. Passepartout tells Fix that, while he’s happy to be saved, he wishes the boat could have arrived half an hour later. Fogg is overjoyed to leave the island—but he also tells his friends that he’ll never forget the time he spent there with them.