Homer watches television coverage of great moments in Olympic history. When he realizes that Carlos Lopez became the oldest Olympic marathon runner at age 38, he vows to enter the Springfield marathon. As the race gets underway, the hopelessly out-of-shape Homer is quickly outpaced by the rest of his fellow runners. Homer nonetheless manages to keep up a steady pace from the rear. When his body gives out, he runs into a first aid tent, where Dr.Hibbert gives him a shock using defibrillator pads. Wearing the device like a backpack, Homer again joins the race, giving himself shocks every few feet. Meanwhile, Bart learns that the grand prize is a walking tour of Springfield. Donning a Chico Marx-style hat, fake moustache and bad Italian accent, Bart emerges out of nowhere to challenge the other runners. But after Bart wins the competition, a passing bird snatches off his moustache, exposing his fraud. As an angry crowd advances, Bart accepts a ride from a passing stranger, a hip-looking man we will come to know as L.T.Smash.

After Smash drives Bart back home, he reveals that he is a record producer looking to create the latest all-boy band sensation. He turns to Bart, Milhouse, Nelson and Ralph for help. After the boys get a complete makeover, Smash uses a recording “voice enhancer ”to give them singing voices. Before long, the group, now called the Party Posse, is performing before a group of their peers in the Springfield Elementary auditorium. The group receives an enthusiastic welcome, and soon after, records its first music video, which is set in a Middle Eastern desert. Lisa notices something odd about the video, and after analyzing it using the “reverse” button on the TV remote, discovers that some of the Arab women in the video speak the words “Join the Navy ”in reverse. Lisa realizes that someone is using subliminal messages to recruit young people into the Navy. Soon after, brainwashed men throughout town have the sudden urge to enlist.

Lisa makes her way to Smash’s office, where she announces that the government is placing subliminal messages in the producer’s videos. But when Lisa notices a Navy tattoo on Smash’s arm, she realizes that it is he who is responsible the evil scheme. She races home and informs her family about the discovery, but Bart and her parents react with apathy. Homer, Marge and Lisa make their way to a mothballed aircraft carrier, where the Party Posse performs a musical number for its adoring fans. Meanwhile, an admiral informs Smash that the Navy is shutting down Project Boy Band. He shows Smash an advance copy of MAD magazine, which lampoons the singing group. As a result, the Navy is certain that the Party Posse’s days are numbered. Smash grows enraged and turns the floating museum into an active aircraft carrier. The vessel sets sail for New York City, where Smash fires upon the humor magazine’s headquarters. Missiles destroy the building, but MAD magazine’s staffers miraculously survive the attack. After police take Smash into custody, Bart realizes with great disappointment that the singing group almost made the cover of MAD. Meanwhile, Homer races the aircraft carrier across the ocean, bouncing it like a speedboat.