In the style of VH1 show "Behind the Music", this documentary takes us back to the beginning of the show, which was apparently a fictionalized, staged version of the life of the "real" Simpsons family, as performed by them. We see Homer's shoddily directed 'pilot' episode before Homer becomes addicted to prescription drugs, Marge makes bizarre business investments, and Bart goes to rehab. The show is put on hiatus after the family/actors split up, and Lisa writes a book about her ordeal. A phony awards show manages to reunite the Simpsons.
Done in the style of "Behind the Music", the popular VH1 biography show, this non-canon episode begins with the Simpson family history and how they got into show business. The first part of the mockumentary follows the family from their weak beginnings to their exceptional prosperity. A television show, a recording contract, a lot of awards, and countless wealth follow Homer's inadequate video "pilot."
However, problems begin to arise as the Simpsons' fame continues. After a funny stunt causes him injury (the cliff plummet from "Bart the Daredevil"), Homer becomes addicted to prescription painkillers, Marge makes some senseless business investments (Marge Simpson Diaphragms, for example), and Bart goes to rehab. Later, the IRS examines soon after they are alerted via Apu (whose voice is only heard) and takes away their house (called "Homertime", since it belonged to rapper MC Hammer before he went bankrupt and was called "Hammertime"). Then, the family gets into a big dispute and splits up at the Iowa State Fair.
Fox is forced put the show on hiatus, since none of the Simpsons will talk to each other. The members go their independent ways: Homer follows a career in the theater; Bart replaces Lorenzo Lamas as the star of the syndicated action show Renegade; Marge makes a nightclub act, and Lisa writes a tell-all book about her experiences on the show. Bringing the family back together seems hopeless until country singer Willie Nelson puts on a phony awards show in order to reconcile the family (and also patch matters up with Van Halen and Sammy Hagar). At the award show, Willie calls out the whole family to present one award. Lisa deduces that the award show is fake and they refuse to even look at each other. However, after Willie and the audience encourage them, they hug and forget past wrongs in a sensitive reunion. Again, they look with hope to the many years of episodes of The Simpsons to come... or not.
The final images show Homer giving orders regarding the editing of "the last season" of the Simpsons series. The sentences we can hear on the editing screen were used for Season 12's last episode, "Simpsons Tall Tales".
At the end of the episode, Forbes names the state that the Simpsons live in as Kentucky, the writers didn't understand how many more years the series would run so they finally chose to reveal it in this season finale.