Jimmy is in training for the upcoming Special Olympics and he's determined to win at any cost. Meanwhile, Cartman decides that he can easily take first place if he can convince the qualifying committee that he's handicapped.
Cartman decides to fake being disabled and beat all the handicapped children in the events and win the $1,000 prize.
To pretend to be handicapped, Cartman undergoes a rigorous, "Push It to the Limit" montage, training regime of sitting on the special education bus while taking notes of how "retards" act, cutting his hair badly, studying a Kid Rock performance, modifying his shoes so it looks like he has a club foot and putting on a bicycle helmet too tight so his face is badly deformed. Cartman's plan works, at least to a point. He gets his mom to take him to the Special Olympics
Meanwhile, Jimmy takes steroids and ends up in a steroid temper, which causes him to be very violent to the point of attacking his girlfriend, (Nancy) and his mother (with Samuel Barber's "Adagio for Strings" playing as the atmospheric soundtrack as he loses his mind). Jimmy's training partner and best friend Timmy frowns on Jimmy's behavior, but being unable to say anything other than "Timmy!!" and "Jimmy!!", he was unable to explain the situation to the school counselor, Mr. Mackey.
Throughout the episode, Kyle tries to talk Cartman out of his plans. Kyle hates Cartman and has always seen him as a thoroughly ruthless boy, but Kyle sees Cartman's plans as so horrible that he seriously worries that Cartman will go to hell for his antics in this episode. He even goes as far as to call himself Cartman's friend. Cartman doesn't pay Kyle any attention, believing that Kyle is not in a position to preach morality because he is Jewish.
Cartman's plan of course fails, having failed to consider that the handicapped contestants all had months of intensive training and are in great shape while he was not. He comes in last in the Special Olympics. However, he gets a spirit award in the form of a gift voucher to Shakey's Pizza. When he comes up to the stand to collect the prize, Jimmy realizes Cartman has been faking his "retardation" and ironically is about to beat him up for being a cheater, but Timmy scolds him for it. Jimmy learns his lesson, namely that taking steroids is cheating, on a par with pretending to be "retarded" in order to participate in the Special Olympics. This results in him giving back his medal and delivering a heartfelt speech to the audience, who applaud him for being honest.
The episode ends with Cartman trying to convince the rest of the Boys that he was pretending to be retarded in order to teach Jimmy a lesson about steroids. The boys, however, do not fall for his deception. This results in Cartman telling them to "grow up", as he walks away.