When producers Craig Zadan and Neil Meron began working on bringing Hairspray from Broadway to Hollywood, they had a secret weapon—a calendar. Not one of the January-to-December variety, but a schedule with days and weeks mapped out for all the special needs of a movie musical: singing lessons, choreography, recording sessions for all the songs.

Zadan and Meron, partners in the California-based Storyline Entertainment, were confident their calendar was sound. After all, they’d developed the system over 15 years as the most prolific producers of musicals in Hollywood. In the beginning, they made it up as they went along, as when they brought Gypsy to CBS television in 1993. In the intervening years they’ve honed their system with a handful of television musicals and the Academy Award-winning film Chicago.

Now they’re hoping all that experience pays off when Hairspray opens Friday on 3,000 movie screens across the country. If the movie is a success—and the early buzz predicts it will be—it will undoubtedly spur Hollywood to invest in more Broadway adaptations. And Zadan and Meron are ready for the calls from would-be producers seeking guidance.

“The difficulty for producers who have never produced a movie musical is that without having the experience of doing all the ones we’ve done, you wouldn’t have any idea how to put together a production like this,” Zadan, 58, says. “We joke that we should rent ourselves out as a movie-musical consultation company.”

Since Chicago was released in 2002, earning $306.8 million worldwide to become Miramax Films’s highest-grossing movie, a number of Broadway musicals have made the leap to Hollywood. Only one of these adaptations, last year’s Dreamgirls, was seen as a critical and commercial success, earning $154.6 million and two Academy Awards. But other shows that were hugely popular onstage failed to bring in many moviegoers: Rent, the rock musical about New York City bohemians, had a $40 million budget but grossed $31.7 million; and The Producers, the Mel Brooks farce that won a record-breaking 12 Tony Awards, cost $45 million to make and racked up only $38.1 million in global ticket sales.

Tom Sherak, a partner at film-production firm Revolution Studios and an executive producer of Rent, says that looking back, perhaps they waited too long to film a story with AIDS as its central theme. “It was eight years too late in the making. I think the world changed,” Sherak says, adding that while the movie attracted those who loved the stage show—the so-called Rentheads—it didn’t do enough to find a new audience.

Zadan says he and Meron passed on producing Rent years ago. “We had absolutely no feel for it as a film. . . . If you don’t have a vision, it will fail,” he says.