When the Simpsons' plans for a nice family outing at the Frying Dutchman turn into a dining disaster (due to an uncooperative octopus armed with knives), the family tries to salvage the night by telling three nautically themed stories.
Bart, Lisa and a widowed Marge board the Mayflower to head for the new world. Homer, fleeing from the police, boards the ship and hides in a barrel. Homer is immediately attracted to Marge, however, Moe (who killed Marge's previous husband), schemes to marry her, and is instantly jealous of their friendship. Moe takes Homer down to the storage room to play a drinking game, taking a drink whenever a wave hits the boat. Homer and the rest of the crew get drunk, and Moe claims that Homer is responsible, leading Captain “Flandish” (Flanders) and Reverend Lovejoy to place him in a stock.
A storm approaches, and Captain Flandish is knocked unconscious. Homer claims that he steers better when he's drunk, and leads them safely out of the storm. Homer and Marge get together, and the members of the Mayflower meet the Wampanoag tribe and join them for the first Thanksgiving feast.
The Bounty sets sail from England in 1789, commanded by Captain Bligh (Seymour Skinner). During the first 718 days of the voyage, Bligh severely mistreats his crew, not giving them water and discarding their mail. Willie warns him of a mutiny if he continues, but Bligh ignores him. They arrive in Tahiti, where Homer and Marge are the rulers of island, and the crew have a wonderful time until it is time to leave.
Bligh continues to abuse the crew, leading First Mate Bart Christian, to begin a mutiny, sending Bligh and Willie off in a lifeboat. Bart, as the new Captain of the Bounty, orders the crews to set sail for Tahiti, but after throwing away the ship’s helm, they end up in Antarctica.
The final story is told by Homer and a parody of the 1972 film The Poseidon Adventure, taking place on the luxury liner S.S. Neptune on New Year’s Eve during the 1970s. At midnight, Captain Burns fails to notice a massive freak wave, which hits the bridge, capsizing the ship and killing most of the passengers. Led by Selma, survivors Homer, Marge, Bart, Lisa, Lenny, Carl, Comic Book Guy, Old Jewish Man and his wife, and Sideshow Mel ignore Purser Wiggum’s advice to stay put in the ballroom and decide to climb up the decks to the engine room. While climbing up through the smokestack, Lenny panics and falls to his death.
Comic Book Guy swims through a flooded deck to help the others get to the engine room, but he has a heart attack and dies. The group makes it to the engine room, but Sideshow Mel’s hair is set on fire by a blowtorch from the rescue team, and he dies. The rest of the group makes it off the ship, at which point they encounter the walking skeletons of the Bounty crew who are still trying to get back to Tahiti.