Bart finds a credit card application amidst a pile of junk mail. Using the name “Santos L. Halper,” he completes the agreement form. Several weeks later, Bart receives a credit card. He uses his line of credit to purchase a variety of items from a catalogue company—including a fully trained, blue ribbon, twelve-hundred-dollar Collie named Laddie. The Simpsons fall in love with the impeccably-mannered canine. A representative from the credit card company contacts Bart demanding payment for an unpaid bill. Soon after, a pair of credit card company goons arrives at the house to repossess all of the merchandise. The last item on the goons’ list is a twelve-hundred-dollar dog. Unwilling to lose Laddie, Bart fools the goons by substituting Santa’s Little Helper.

Bart realizes he made a terrible mistake. He gives the Collie to Chief Wiggum after the dog saves a baby’s life, then traces Santa’s Little Helper from the Repo Depot to the home of a blind man named Mitchell. Bart breaks into Mitchell’s house one evening, intending to steal away the dog. But Mitchell catches the boy in the act. Believing the dog will come to the owner who loves it most, Mitchell and Bart call the dog’s name. After chasing its tail in a circle, Santa’s Little Helper approaches Bart.

Wiggum, accompanied by his men and the Collie, arrive at Mitchell’s home, intending to arrest ‘the burglar.’ The Collie takes an immediate liking to Mitchell—and locates a packet of marijuana on his person. Mitchell claims the drug is used strictly for medicinal purposes. Wiggum instructs Bart to leave the premises. After Bart leaves, the police have a party at Mitchell’s home.