The Simpsons take in a show at the Magic Palace, a castle-like building featuring magic acts. A waiter brings Marge a Long Island iced tea. After consuming the drink, Marge grows tipsy, and ventures on stage when Diablo, a magician, asks for a volunteer from the audience. Diablo gags Marge and places her inside the “Kill-o-tine,” four guillotines lined up in a row. The blade descends, Marge vanishes…and four chimps dressed in Marge’s clothing jump out of baskets near the device. The audience cheers. Afterward, Bart convinces Homer to purchase him a magic kit from the gift shop. During the drive home, a huge fish falls from the sky—courtesy of two cosmonauts arguing in a Russian space station—and damages the Simpsons’ car. The next day, a mechanic informs Homer the repair will cost $6500. Bart and Homer decide to raise some cash by performing magic acts at the Squid Port. But the idea fails and Homer walks away with 60 cents. Soon after, an argument erupts between Homer and Bart. Homer drives off in a huff, leaving Bart at the Squid Port. It isn’t long before passersby take pity on the poor “street urchin” and begin dropping coins into Bart’s hat. When Bart returns home with his earnings, Homer decides there’s money to be made in grifting. Homer and Bart return to the Squid Port, where they pull off a series of cons. When they return home, a suspicious Lisa asks them how they could have performed any magic without the aid of the magic kit. Bart and Homer dismiss her concern, but Lisa remains convinced that something is amiss.

Homer and Bart return to the Squid Port, where they con Dr.Hibbert out of money by pretending Bart’s dog was swallowed by a shark. Armed with the loot, Homer pays for the car repair. Despite this, the pair decide to continue their scheming, and attempt to sell Ned Flanders a fake Bible, a la Paper Moon. When the plot is exposed, Homer and Bart take refuge in the backyard tree house, where Grampa reveals that he wrote the book on flim-flaming. The threesome turn their attention to the retirement home, where Homer and Bart, disguised as the “Prize Patrol,” present Grampa with a ten million dollar grand prize. Suddenly, Grampa falls over, faking his own death. The other retirees are told that they could end up with the money, but only if they cough up the “wealth transfer fee” of $100 per person. The oldsters fall for the ruse and Homer makes off with a sack of cash. Suddenly, a Silver-Haired Man steps forward, identifies himself as an FBI agent and places Bart and Homer under arrest.

The FBI agent drives the pair to the local police station in the Simpsons’ car. Once Bart and Homer enter the building, the FBI agent, who is really a scam artist, makes off with the car and the sack of cash. When Bart and Homer return home, they tell Marge that they were carjacked in the church parking lot by a foreigner with bushy hair. Soon after, Groundskeeper Willie is arrested for the crime. A trial is held…and Willie is sentenced to ten years in prison. Protesting his innocence, Willie grabs a gun from Wiggum’s holster and shoots Skinner. Homer turns to the crowd and announces that he and Bart concocted the story about a carjacking. Suddenly, Marge and Lisa reveal that the entire Willie trial, Skinner’s phony death and the FBI agent carjacking was their scam, put together to teach Homer and Bart a lesson. Afterward, Homer and Bart insist they, too, were in on the scam from the very beginning. Later, all the scammers surf an ocean wave.