True fans of FOX's "The Simpsons" know that Matt Groening may be the series' creator and James L. Brooks may be the executive producer with the Oscars on his mantle, but if you really want to discuss Springfield's favorite yellow family, Al Jean is the guy you want to talk to.

Jean has been with "The Simpsons" from its humble beginnings, serving two tours of duty as showrunner, a job he's held since Season 13.

"The Simpsons" returns for its 21st season on Sunday (Sept. 25) night, which seemed like the perfect time to chat with Jean about the show's ongoing anniversary celebration, the transition to high definition and, of course, the premiere, which was co-written by "Superbad" and "Pineapple Express" scribes Seth Rogen and Evan Goldberg.

 

HitFix: I always like to get a bit of perspective. We're starting Season 21 on Sunday, but where are you guys in the writers' room now?

Al Jean: The show that we're going to read tomorrow is the Halloween episode for next fall. We've recorded the initial records for all of the episodes that will air in Season 21.

 

HitFix: So focusing on this Sunday's premiere, how did Seth Rogen's involvement come about?

AJ: Jim Brooks was meeting with Seth, although it didn't pan out, to work on the movie that Jim's shooting now. Seth said that he would love to write an episode and they came in and Seth had this idea that Comic Book Guy creates a comic whose hero gets the power of every comic book he touches. He mentioned that on "Green Hornet," they start working you out to get you in what they call "superhero shape" and we thought it would be funny if Homer were the star of the film and you had trainer who got him in shape and then he got fat and the movie was completely messed up.

 

HitFix: Did Seth and Evan have to go through the same table staff process that other writers would have to go through?

AJ: Oh, completely. Yeah. The two outside celebrity scripts that we've had have been by Seth and Ricky Gervais and the one rule I had was that you get treated no better or worse than any other writer.

 

HitFix: Given how collaborative the "Simpsons" writing process has always been, is there really any opportunity for an individual voice to come out?

AJ: Well, I always say that no matter who's script it is, the most you can have in any script with your name on it is 30 percent. The collaboration just makes it so much better and it's exponentially improved by the number of people who are involved.

 

HitFix: Given that rule, then, how would you say that this episode is a Seth Rogen/Evan Goldberg script?

AJ: It's a Seth Rogen/Evan Goldberg "Simpsons" script. It's a little more like our "Simpsons" episodes than it is like "Pineapple Express," but it's a collaboration, like any other collaborative process.

 

HitFix: How have the writers in the room responded to these two celebrity writing cameos?

AJ: Everybody really liked Seth and really liked Ricky, so we were happy to have them. Both of them are such down-to-Earth people that when you're working with them, there's no pretense and you just treat them like you would any other writer that's funny.

 

HitFix: So if you had a wish list, are there any other big-name writers you'd like to get "Simpsons" specs from?

AJ: That's funny. Well, Conan O'Brien. That would be great.

 

HitFix: But we know what a Conan O'Brien "Simpsons" episode sounds like.

AJ: It's an interesting question. You know, somebody who I think is a brilliant writer is Alexander Payne. He's not exactly an on-camera celebrity, but he's somebody who... I don't know if he'd do an episode of "The Simpsons," but I think he's one of the funniest writers there is... Ummm... Who else is really funny? Steve Martin's really funny. He's been on the show as a voice, but not as writer.

 

HitFix: Obviously at this point, 21 years, you guys have done everything and in this episode, there are a lot of familiar elements. Homer gets in shape. They make a movie in Springfield. Etc. Is there a rule to how you guys can use familiar elements without repeating yourself?

AJ: Well, we've 400 and, this is Episode 442, I believe. So it's impossible to never tough on anything that we've ever done in any other episode. On the other hand, we never want to do a joke the same. We never want to tell a story in the same way. We want make it contemporary. What made me think this would be different is that superhero movies have taken over Hollywood. "The Dark Knight" is just an example of how they've become the biggest thing ever. So what we wanted to do here was to show Hollywood is so desperate to anything that has a superhero's name attached that they'll really bend over backwards to make something that's pure dreck just to get another superhero movie out there.

 

HitFix: Stepping back and looking more generally, how has last season's shift to HiDef changed the production process?

AJ: Well, we really didn't pay a lot of attention to backgrounds. For example, in the episode that we premiere with, see the movie posters in the background for like "Star Wars: Episode 10 - The Apology" and "Alvin and the Chipmunks: Gettin' Rabies" or "Swatchmen." We would always have problems doing those before because it was very hard to get a consistent background with lettering from scene-to-scene. With HiDef now, we can finally really devote attention to every inch of the image and I think the animators have done a terrific job, as you can see with the new main titles, of just making it look interesting and beautiful. And we can use our history to our advantage, where we throw in little things that reward the persistent viewer of the show, references from other episodes that are small and don't necessarily impact the plot, but are there if you're looking for them.

 

HitFix: Does this add extra time in the process, or would these be jokes people already would have been tossing out there?

AJ: It always takes extra time. Time is the the thing that I always wish we had more of. It just means you have to write a lot more. They'd say, "OK. We're going to go to the Kwik-E-Mart. Please write all of the video games that will be in the background and any products that you want to see." That takes you several hours that you wouldn't have spent before, just detailing thoroughly. And part of it, too, is that you don't want to have a million word jokes where you see something and you keep seeing something and you get sick of it. You want to have images that you don't get tired of and that don't interfere with the story, but on the other hand are funny for people who are looking for them. So it's just the process of rethinking like Moe's and anywhere else that the Simpsons might go and then trying to say, "How do we make it look like the show was designed today and not 20 years ago?"

 

HitFix: Was it amazing when you first saw how good the show could look?

AJ: Oh yeah. The first time I saw it was when I worked on the movie. But there are some things that aren't so good that it highlights, which we've been trying to take care of. For example, if you have a little note in the background and somebody's scribbled on it, it used to be that the whole show looked like it was from a cartoonist's pen, so that was OK, but now you really have to block everything out and make either a geometric design or write what's on it. But there's no going back and it's great. The digital coloring, also is huge. Formerly if we had something, like seven years ago, that was the wrong color, you were stuck with it. You had to repaint all of the cels. Now you can just change it in the computer and do it for a smaller cost.

 

HitFix: So how are you participating in this "Best. 20 Years. Ever." Anniversary celebration the show is doing?

AJ: A few ways. Matt [Groening] and I, we're doing a two-hour block. We hav the one-hour documentary by Morgan Spurlock, which I participated in. We had a contest Morgan and I, plus Matt Selman, were the judges trying to find the biggest "Simpsons" fan ever. I've worked with him and I think he's great. We want sort of an outside-inside look. We wanted to do a history of the show, but not to take ourselves too seriously and to be more interested  in "Who in the world has the most 'Simpsons' tattoos?" or "What does the world look like if you're inside a Homer suit?" And then the rest of the night, the second hour, is two new episodes, one starring Anne Hathaway, in which she sings and she's brilliant, and then another good episode with Chris Martin of Coldplay. And then there's a contest that ties in with it where a fan gets to create a new character that we'll introduce in the second episode of the night.

 

HitFix: And was Comic-Con a productive place for y'all to go in search of the biggest "Simpsons" fans?

AJ: It was definitely entertaining. What was most entertaining was that you'd meet these guys who would be like 50-years-old and they'd say, "I'm a real-life Homer Simpson." And I'd say, "Really, what do you do?" And he goes, "Well, I work on safety systems for nuclear submarines." And I'd go "Oh God."

 

HitFix: As a last question... Has the resurrection of "Futurama" impacted Matt's availability to "The Simpsons" at all?

AJ: I think we actually see him a little more, because the "Futurama" episodes are right down the street from ours, so when he's done there, he comes back here and vice versa.

 

HitFix: So he's still a presence, Jim Brooks is still a presence, etc?

AJ: Why tinker with a formula that's succeeded so well?

 

"The Simpsons" returns to FOX on Sunday, Sept. 27 at 8 p.m.