Trey Parker and Matt Stone on The Book of Mormon

Richard Rodgers attended Columbia University with his future musical-theater collaborator Oscar Hammerstein II. Leonard Bernstein and Adolph Green (On the Town) were co-counselors at a Jewish summer camp. And what brought together the collaborative team of The Book of Mormon, the smash-hit musical comedy that won nine Tony Awards in 2011 and opens a dedicated Chicago production this week? An interest in prurient puppets.

South Park honchos Trey Parker and Matt Stone were in the planning stages for their 2004 film Team America: World Police, an action-movie spoof peopled with marionettes, when Avenue Q, the adult-oriented puppet show authored by Robert Lopez, Jeff Marx and Jeff Whitty, made a splash Off Broadway, eventually transferring to Broadway and winning three Tonys. In 2003, Parker and Stone went to see Avenue Q—on a night Lopez happened to be in the house.

“I was really excited to see them, because they’re heroes of mine,” Lopez says. Stone and Parker’s work on South Park had influenced Avenue Q to the point that the two men were thanked in the Playbill.

The three went out for drinks after the show, and conversation turned to future projects. “I mentioned that I had this idea for a show about Mormons,” Lopez recalls. “And they said, ‘No way, that’s crazy. That’s sort of what we want to do, too.’ ”