Troy McClure hosts this episode, which highlights individual scenes and sequences from throughout the show and offers never-before-seen outtakes. McClure starts the episode by showing a brief presentation of how The Simpsons series was conceived by Matt Groening, James L. Brooks, and Sam Simon. He goes on to present some clips of the original shorts that aired on The Tracey Ullman Show, including the first one, "Good Night", in its entirety. Next, a presumed commercial break is introduced with a trivia question about the message that appears when Maggie Simpson is scanned by the cash register during the show's opening sequence; the answer is revealed (falsely) to be "NRA4EVER." The show then returns to McClure, who responds to questions from fan mail by showing clips that contain the answers. The letters include questions on Homer's growing stupidity, how the cast and crew can create an episode per week, and hints of Waylon Smithers' homosexuality.
Another commercial break is then introduced with a trivia question, this time concerning which two popular characters have died within the past year; the answer is revealed to be Bleeding Gums Murphy and Dr. Marvin Monroe, although neither of them were ever popular (and the latter was not actually dead, as revealed in "Diatribe of a Mad Housewife"). McClure then presents deleted scenes from Simpsons episodes, "Krusty Gets Kancelled", "$pringfield (Or, How I Learned to Stop Worrying and Love Legalized Gambling)", "Mother Simpson", "Treehouse of Horror IV", "Homer and Apu", and "Burns' Heir".
McClure also reveals that alternate endings to part two of "Who Shot Mr. Burns?" were created to prevent the staff on The Simpsons from spoiling the mystery that "all of America was trying to solve [...] this past summer". These alternate endings, most of which consist of random characters shooting Mr. Burns, conclude with a more elaborate ending in which Smithers is revealed to be the assailant. Troy McClure ends the episode by showing a montage of "hardcore nudity" (scenes of The Simpsons characters naked), set to the KC and the Sunshine Band song "(Shake, Shake, Shake) Shake Your Booty".