Last night marked the season premiere for the 20th season of South Park, and the show continued to be one of the funniest on television. As the show celebrates 20 years, Hollywood Reporter sat down with basically everyone they could find for an all-encompassing interview on all things South Park.

Among those interviewed was Primus bassist Les Claypool, who wrote and recorded the theme music for the show. That theme has remained unchanged for the show’s 20 year career, but, apparently, it wasn’t music that Claypool has planned from the outset.

Claypool tells the story in the interview, with interjections from show co-creator Matt Stone to round out the full story.

Claypool: We got a call years ago that these guys were working on this little animated pilot for Comedy Central. They were a couple of college kids who were fans of the band, and I guess they approached me to do the theme song. At the time, Primus had just gotten a new drummer, so I said, “Let’s have Primus do it.” We had watched their Christmas thing that was going around, and we realized these guys were pretty clever, but there was no way in hell that they were going to be able to get something like that on television. More than anything, it was just an excuse for us to go into the studio and start experimenting.

Stone: We wanted Primus to do the theme song, and then we needed a change. And we were like, “F—!”

Claypool: If you listen to the outro, that’s actually the original song. And they came back to us and said, “Comedy Central thinks the theme song is too slow and not peppy enough.” At that point, we were like, “You know, we did this for you guys, we’re out on the road, we’re too busy to do this right now. We can’t just go into a studio and rerecord this.”

Stone: We couldn’t get their management to talk to us. They were like, “F— you, dude, take the song.” Not from Les, but from the management. So I actually went down to Irvine and went backstage and found Les at this concert, and I was like “You have to record it.” I got in his face. And he was like, “I’m on tour. I can’t.”

Claypool: So they just sped it up and I redid my vocals. I believe I was playing Red Rocks [in Morrison, Colo.] and they sent one of their old high school chums up with a handheld tape recorder, and I just did my vocals into that.

Stone: It was really awesome he did it.

Fortunately, everything worked out in the end, and Primus has remained an integral part of the South Park experience for 20 years! Here’s to the next 20…