"Trapper Keeper" is the twelfth episode of Season Four and the 60th overall episode of South Park. It aired on November 15, 2000.
Cartman gets a new Dawson's Creek Trapper Keeper Ultra Keeper Futura S 2000 that blows Kyle's Trapper Keeper out of the water. When he finally stops bragging, a stranger informs him that it will eventually fuse with other computers into a powerful super being, take over the world and destroy humankind if they don't destroy it first. Cartman refuses to accept that he must live without his Trapper Keeper and becomes infused with the high tech folder. Kyle must do anything he can to separate the two and destroy the super being.
Kyle takes a Dawson's Creek Trapper Keeper with him to school and is soon met by Cartman. Cartman brags about his Dawson's Creek Trapper Keeper Ultra Keeper Futura S 2000, of which shows off many features that far exceed Kyle's. A mysterious man going by the pseudonym Bill Cosby approaches them and asks Cartman about Trapper Keeper, which he then attempts to steal. He is caught by Officer Barbrady and Cartman. "Bill Cosby" then explains that the binder is a means to conquer the world in the future and wipe out all traces of humanity. "Cosby" himself is a cyborg from the future named VSM-471 with the task to destroy the binder. Cosby manages to destroy it but Cartman buys another which, according to the laws of time travel, would be the one that is actually destined to destroy the world. Furthermore, Cartman refuses to allow this one to be destroyed.
Meanwhile, Mr. Garrison, having been demoted to a kindergarten teacher, oversees his class' election for class president. Ike runs against a boy named Filmore, the result being a tie. Unfortunately, the only tie breaker can be achieved through an indecisive girl named Flora. Flora eventually makes a decision, however the kids protest about an absent student, demand recounts, involve Rosie O'Donnell (who protests about her nephew losing the vote). While this is going on; Stan, Kyle and Kenny try to convince Cartman's mother to help them, however she soon takes VSM-471 off to have sex. Cartman's Trapper Keeper, meanwhile, integrates itself into Cartman's computer and most of his belongings, then absorbs Cartman himself, becoming a twisted bio-mechanical monster with some of Cartman's features. The boys try to break the door down but Kenny, attempting to run and smash it down, gets crushed against the wall. The Trapper Keeper monster sets off to Cheyenne Mountain to a secret military base to try and absorb its computer to become unstoppable.
After hearing farts coming from an exhaust tube, Stan is glad to know that Cartman still has some free will.
Kyle carefully makes his way into the beast through a ventilation pipe. However, before he can disable it the creature incapacitates him. Rosie O'Donnell appears shouts at the creature for blocking the road, which leads to much confusion over which one is the amorphous blob. The creature absorbs her but is made weaker because of it. Kyle is freed and disconnects the Trapper Keeper's CPU, returning it to a powerless state. TVSM-471 becomes nonexistent as he is not needed to be built in the now safer future. Stan tells Cartman to thank Kyle, who just saved his life. The credits roll before he can do so, cutting him off.
As for the kindergartners, after countless lawyers, legal forms and endless meetings, Filmore concedes after becoming bored of the idea. With Ike as president, the kids decide to go fingerpaint. Garrison relieved at the return of normality.