From their first movie,

Cannibal: The Musical, to the South Park movie to the montage in Team America, Trey Parker and Matt Stone are no strangers to mixing music with their particular brand of humor. And tonight their latest endeavor, the Broadway musical The Book of Mormon, opens after three weeks of packed previews. In the midst of their busy schedule putting finishing touches on the show (which follows a group of Mormon missionaries in Africa) the duo talked with us about the difference between making a movie and a live musical, their creative process, and if this is the last time we'll see their names up on a Broadway marquee.

Hi there, Just so I can keep track, would you mind telling me which of you is which? [Ed. We know they have very recognizable voices, but it was a crappy phone connection!]
Matt: I’m Matt.
Trey: And this is Trey. We sound about the same.

Before we get to The Book of Mormon—from your work it is clear you guys are well-schooled in musical theater. What are your favorite shows?
Matt: I grew up with musicals and I really love them, so for me it was kind of the classic stuff like the old Rogers & Hammerstein stuff, and movies, too, like Singing in the Rain, that I would sit and watch on VHS tape. But for me, it was the old, cheesy, happy-go-lucky musicals that I really loved growing up.

How was writing a musical for stage different than writing musicals like Cannibal or the South Park movie?
Matt: How is it different? Well a lot of it, like the actual song-writing part of it, you kind of have to visualize what it would be with the limitations. You’re like ok, in the middle of the song—for instance, in the South Park movie, we do a thing in the middle of the song, Kyle’s Mom’s a Bitch, we go around the world and have all these people come in and you can do these cuts really quick; on stage you have limitations. I think the song-writing is really similar, but in the process of refining it you have to do workshops and hire actors and put on little readings. You just don’t know until you watch people do it back at you with an audience. Whereas the stuff that we’ve done before is really just Trey and I sitting in a room with an Avid editing machine and doing it in an insulated kind of way. It is really about the differences. You have to have that audience and you have to sit back and watch people live do it. It’s definitely a different feel.

And the two of you are sharing credit for the book, music and lyrics with Robert Lopez in this one—how did you split up the work between the three of you?
Trey: It kind of naturally split up once we were in the room, but we wrote the whole—the music was written with the three of us in the room.
Matt: This is Matt—I would definitely say that Trey and Bobby are the songwriters of the three of us more than me. Bobby’s an amazing piano player, Trey’s a great singer, I play drums, and our engineer played guitar. For just that first part—until we started having to do workshops and brought in Stephen Oremus [the music director]—just those first demos, we would just get together and start jamming. Trey would have his computer and we’d be kind of spitballing ideas and playing kind of in a little band, and hit record and putting it into ProTools and editing it. Really, there hasn’t been much—one of the big things, it’s weird to us, the separation between book and music and lyrics on Broadway. Because for us from the start it was kind of all written together.

How long have you guys been working on this?
Trey: It’s been about seven years, and part of that is because twice a year, we have to put it down and go create a bunch of episodes of South Park. We’d put this down and completely forget about it, and then—that was the nice thing about the fact that we were creating songs instead of just writing script, because we’d get to the end of the South Park run and rest a little bit and then we’d listen to the MP3s of the songs we had, and it would always excite us again and we’d go, "Oh this is pretty good, let’s just do one more song, let’s do one more song!"

Because Bobby was out on the East Coast and we were in LA, so we were like, "Let’s just get together and write another song or two."

So we would just do that in spurts for the longest time. And then finally when we started doing workshops is when we started writing a lot of connective tissue and making it an actual cohesive project. Even if it hadn’t been for South Park, it probably still would have taken quite a while, but it definitely took longer because of that.

What made this season the right one to do the show? Was it just that it felt right in workshops or was there a push to get this done?
Either Trey or Matt: After [the workshops], we were like, you know, we felt good about it, we felt it was pretty strong. We got to a workshop where we got a great reaction and we just knew it was either time to really hone it in and kick our own butts and get it going or we were just going to get sick of it.

So you guys have been here through pretty much all the previews and everything?
Both: Totally, yeah.

Some creatives I won’t mention have been absent from their show's previews... How does the preview process differ from having a screening of your movie or TV show?
Matt:It was terrifying for me because even with episodes of South Park, I’m kind of going so out of my head while we’re doing each show as we’re creating it. I don’t sit down and watch the whole thing of what we have until it’s done—actually, until way after it’s down. And with movies I’ve never really believed in test screenings. And so, this was the first time that it was just like, there was really no choice but to sit there, because the audience is so much more an integral part of the show, that you had to sit there with a bunch of live people and live performers, and just be really emotionally terrified—just go and be terrified once a day for three weeks.

Rema Webb, Andrew Rannells and Josh Gad in the Book of Mormon (Joan Marcus)

Have you been making changes based on people’s responses?
Either Trey or Matt: Yeah, totally. A lot of the changes we sort of knew anyway. A lot of times the audience just supported our thoughts. Like a part that we knew wasn’t great wasn’t great, or a part that we knew was great, was. But it was also just still a lot of logistical things, and just like a movie it was tightening, and you know, stuff like that. Watching every day, trying to do that—because in South Park we can change an episode so much in one day. One day on an episode of South Park can change the entire episode.

Well, you guys have a famously fast turnaround on that, right?
Matt: For this, there was a lot of getting used to that. At the very beginning, we were handing over pages and going, "Here!" Casey [Nicholaw, the co-director] and the cast were like "What the hell are you doing?" There was that give-and-take everyday, too, trying to learn how to get the changes in we wanted and trying not to overwhelm anybody. Luckily, because of the time we had taken and because we’d done a lot of workshops in New York and really put our time in, we came to it with a thing that was 94% there and we just tried to take it that last bit.
Trey: After being through this process, I can’t imagine getting into the previews and being like "Oh wow, that whole last number, we have to re-write that whole thing." Which I guess happens on shows?

Well, Spider-Man opened without a last number.
Trey: That sounds like a nightmare.

What kind of feedback have you been getting from the Mormons?
Matt: It’s really interesting because every night that we go, we can sort of tell where the Mormons are in the audience. We’ll hear little pockets of Mormons. We always know because because there is a lot of insider Mormon stuff—not a lot, but enough that when it happens, we hear the Mormons chatter or get a little giddy, and we’re like, "Oh, there are Mormons over there."
Obviously it’s a pretty select group of Mormons that will even come see the thing, so the ones that are going seem to be liking it, but I think the ones that wouldn’t like it aren’t going in the first place.
Trey: It’s a self-selecting group of Mormons that are seeing the show, probably. I’m sure there are Mormons that would be offended but to pay $50-$100 to go be offended you’d have to be a pretty irrational Mormon.
Matt: It’s funny because if somebody made a musical called Trey & Matt Suck, and asked me for $100 to see it, I wouldn’t pay it.
Trey: You don’t go to that show. The Mormons who come to the show are the Mormons who have a sense of humor which is probably 90%, or ex-Mormons, or liberal Mormons, or however you want to say it. The hardcores—I don’t think there are a lot of hardcore Mormons in New York City.

I haven’t seen the show yet, but my impression from the materials I have seen is that you aren’t exactly saying they suck.
Trey: We like Mormons! The Mormons in the show, their spirit saves the day. At the same time, it’s about two missionaries going and trying to spread their religion. It’s about two guys telling these stories, which even to Americans like us sound ridiculous—like about a guy going up on a hill in New York, digging in the ground, and finding golden plates that tell of ancient peoples in America. Like, that sounds really goofy to you and me and normal people. But think of how it sounds to someone in Japan or in Russia or Brazil.

We are having fun with their mythology and their scripture, but the people and their intentions are really good and I think that that’s true of most Mormon missionaries. They are young men who are sent to the other side of the world to spread something that they really believe in and that they believe makes them better people and helps save the world. It’s easy for us cynical adults to look and laugh, but if you try to tell that story from inside, what it would be like to be them, it would probably be a pretty cool coming-of-age story.

Do you have any LDS members in the cast and crew?
Matt: No, we have one guy who’s an ex-LDS, though.
Trey: We gotta get a cast list... There is an ex-Mormon, he loves the show. He’s like, "Yeah! This is kind of like my life story."

As a Cannibal fan I have to ask, is there a cowbell solo?
Matt: No, we should of put one in.

When this is open, do you think you guys are going to do another Broadway show after this?
Trey: Probably not the following week. We’re done for a little while.
Matt: Yeah, we’re done for a while.

And is there any chance of you doing a live-action South Park or a big budget production of Cannibal?
Matt: We’ve been approached about that for years, about both. But we have to be really excited about something in order to commit time to it, and we kind of just move on from ideas. We’re really used to that with South Park—we do an episode and completely move on to a different subject next week. It’s pretty hard for us to backtrack.