Seasons 9-12 saw a lot of changes in the show, and none of them were for the better. Among the people whove kept the flame of fan discussion going since before the turn of the millennium, the most remarked upon is easily the ascension of Mike Scully to the show runners throne for that four-season stretch. Scully has served as a lighting rod for electronic criticism ever since, but he was being handed a show that was already showing its age and was in worse shape than ever. There were two major problems, one subtle, the other spectacular.
The subtle one was the continued unraveling of the writing staff. Scullys time, starting with the 5F production run, saw a number of key departures, many of them to Matt Groenings Futurama, as well as the addition of a number of new names who had never worked on the show before. The spectacular one, a blow from which the show never recovered, was the death of Phil Hartman.
The staff turnover is covered in Chapter 5, and Hartmans death is discussed in Chapter 6, but the specific departures at that time were so huge that they need to be listed to be understood. Scullys time at the helm saw the show not just losing people, but losing people who would go on to create their own hit shows and blockbuster movies. Like a championship sports team that sees its star players sign with other clubs, The Simpsons had more talent on it than any one show could contain. Multiple people that were mere cogs at The Simpsons would go on to run or create some of the most successful and acclaimed comedies of the last decade.
There was David S. Cohen, who would change his name to David X. Cohen when he went off to develop Matt Groenings second animated FOX comedy, Futurama. Hed been with the show since Season 5, and left halfway through Season 10. Futurama, of course, earned its own place in pop culture, as well as enough enduring fan interest to resurrect it from cancellation a decade after its debut.
Then there was Richard Appel, who had worked on The Simpsons from Season 6. He left after the 5F production run, the one that roughly makes up Season 9 and Scullys first as show runner. Hes since worked on or outright run several of FOXs other hit shows, including King of the Hill, Family Guy, and The Cleveland Show.
There was also Greg Daniels, who came aboard in Season 5. Though his last credited episode is in Season 9, he was never on Scullys full time staff. Since leaving the show hes become one of the most successful comedy writers in Hollywood. He co-created King of the Hill, came up with NBCs critical darling Parks and Recreation, and developed the smash hit American version of The Office. Guys like him arent easy to find, much less replace at the same time so many others are leaving as well.
Finally, there was Brad Bird. You might recognize him from beloved animated films like The Incredibles, The Iron Giant, and Ratatouille, for which he picked up two Academy Awards. Bird had been with the show literally since the first episode, and to say that hes an enormously talented guy would be a major understatement. Scully only had him for two episodes before he left for Pixar and the upper reaches of the entertainment industry.
The departures Scully faced werent just from headline names either. Dan McGrath had been writing for the show since Season 4. He left with Oakley and Weinstein at the end of the 4F production run. Jonathan Collier started in Season 5 and was never on Scullys staff; his final credits on the show are from the four episode 3G production run. The same is true of Jennifer Crittenden. She started in Season 6, finished with those 3G episodes, and would later work on Arrested Development. Ken Keeler started with Oakley and Weinstein in Season 7 and stayed only two years before going on to become one of the main writers for Futurama.
Scully hired plenty of new writers, of course, many of them no doubt hilariously funny and deeply talented. But he was being given a show that was crumbling from the inside. By the time you get to the BABF production run, mostly Season 11 and the halfway mark of Scullys four years in the big chair, only a third of the staff had been there prior to Season 7. Two years later, there were only a few writers left who had been there before Scully.
Perhaps most telling is what happened to old time writers who came back to the show, both during Scullys time as show runner and after he handed the reins to Al Jean, who has occupied the position ever since. Jace Richdale and Frank Mula had both originally come aboard during the first transition of the writing staff in Seasons 4 and 5. Jon Vitti and David M. Stern had been there at the beginning. All four of them would eventually return to the show, but never for more than a season or two. A few seasons after Scully left, even John Swartzwelder and George Meyer, the last two writers who had been there continuously from Season 1, finally departed.
Mike Scully was put in an impossible position, essentially asked to reboot the show a second time. He never had Doris Grau, who in addition to her voice work had been the shows script supervisor since Season 1. Phil Hartman died just one season into Scullys tenure. And as if that werent enough, the show was reaching the age where even the most successful programs usually start to wrap things up, which is precisely what his predecessors, Bill Oakley and Josh Weinstein, thought they were doing.
Scully did manage to squeeze out a few great episodes in his time, but no one couldve prevented the show from declining. Too many people who made it what it was had left and too many characters had been through the same adventures too many times. There just wasnt much left to say. The safe and comfortable mediocrity of the subsequent seasons under Al Jean have only served to underline how inevitable the decline really was.