In the tradition of classic musical sequels like Goodbye, Dolly and Seven Divorces for Seven Brothers, the creative team behind Hairspray is set to return for a follow-up slated for 2010. New Line has reportedly brought aboard John Waters — whose original 1988 hit was adapted to a Broadway tuner that grossed $200 million when re-adapted for the screen last year — to scribble a new treatment "[picking] up the Baltimore saga of the Turnblad family after the resolution of the first film, which was set in 1962." Director-choreographer Adam Shankman and songwriters Marc Shaiman and Scott Wittman are slated to return. The original cast is a question mark, however, as Nikki Blonsky, Queen Latifah, Christopher Walken, Michelle Pfeiffer and a frocked, fat-suited John Travolta (among others) didn't have sequel options. But while hardly incidental, such details seem secondary to a far more important question: When has a film musical's sequel ever been a hit?Shankman alludes to as much in an interview today with Variety, citing only the success of High School Musical as a musical franchise that worked. Of course it's a nonsensical analogy; despite the films' common Zac Efron denominator, tweens aren't going to break the sound barrier racing off to Hairspray 2. Pfeiffer has history here, too, as the female lead in another sequel that famously fizzled, Grease 2. Moreover, what would Hairspray 2 even be about? Velma Von Tussle's Aryan revenge? Tracy Turnblad goes off to Johns Hopkins, discovers acid and founds Beehives Against the Vietnam War? Or, better yet, drops out of school and stars in early John Waters films? No, really. We're asking. The possibilities are endless, yet we know there's only one right idea — and with history as our guide, it might be to skip the idea altogether.