At the 2009 Tony Awards, Poison singer Bret Michaels performed his band's 20-year-old party anthem "Nothin' but a Good Time" in conjunction with Rock of Ages, a Broadway musical glorifying the brief but spectacularly ridiculous time in which Michaels and his fellow poofy-haired man-poodles ruled the earth. He then turned around and walked straight into a lowering partition, breaking his nose and knocking himself silly. I can't think of a better metaphor for Adam Shankman's big-screen adaptation of the play: It's a loud, extravagant production that tries to bludgeon you to death. Even the most nostalgic Hollywood barfly would admit that two-plus hours of nonstop pop-metal hits is too much for the brain to take, let alone pop-metal hits that've been given the High School Musical treatment. It's like being repeatedly karate kicked in the temple by David Lee Roth.

Don't get me wrong, the movie isn't an entirely painful experience. For a little while, at least, it exudes a certain innocent charm. There isn't a trace of irony in Rock of Ages. Apparently, the original play was meant as a gentle send-up of the days of Aqua Net and mainstreamed misogyny, but the only winks in Shankman's film are the flirty come-ons between its freshly scrubbed leads (dancer and country star Julianne Hough and Diego Boneta, who I assume once played a baby deer in something). It's a genuine celebration of the big-glam '80s, even though no one involved seems to have any recollection or knowledge of what that period was actually like. Sure, as Sherrie (Hough)—a small-town girl and aspiring singer just off the Greyhound from Tulsa—takes her inaugural stroll down the Sunset Strip, she passes prostitutes and punks, then gets her suitcase stolen out of her hands. Still, there are no back-alley blowjobs or guys choking on their own vomit in bathroom stalls. That's OK, though. Somehow, a totally misremembered, idealized ode to an era defined by blatant inauthenticity feels appropriate.

And then there's Tom Cruise. He plays Stacee Jaxx, the film's resident decadent rock god, who's introduced by emerging from underneath a pile of half-naked women wearing a jewel-encrusted codpiece, chaps and a thong, and tattoos of pistols pointed at his crotch. Cruise embodies Jaxx as a sort of heavily medicated prairie dog, shambling into people's personal space and delivering nonsensical shamanistic proverbs like a zombified Jim Morrison. Like his turn as a foul-mouthed movie exec in Tropic Thunder, the role is Cruise deliberately playing against type, and if he were onscreen much longer, the act would wear out its welcome. As it is, though, it's a legitimately amusing turn.

But oh, Christ, the music. It's not really the songs themselves, bloated and pompous as they are. There's just too many of them. Not two minutes go by without the screen erupting into a lavish performance number, giving the already thin story no chance to breathe and leaving the more dramatically talented members of the ensemble cast—Russell Brand, Paul Giamatti, a horribly bewigged Alec Baldwin—with little to do but primp, preen and, in the case of poor Bryan Cranston, get bent over a desk and spanked. They call these things "jukebox musicals," but this is more like a six-disc Monsters of Rock compilation come to life, with songs literally piling up atop one another. At some point, the performances stop having anything to do with the film at all, existing only for Shankman to show off his choreography skills. By the time the camera pans over the Hollywood sign in the final moments, I prayed a plaid-patterned bomber would appear over the horizon and nuke the entire goddamned city. But then, that'd just give someone another horrible idea. “Coming in 2013: Touch Me I’m Fabulous: The Grungical Musical!” 

Critic’s Grade: C-

SEE IT: Rock of Ages is rated PG-13 and opens Friday at Lloyd Center, Cedar Hils, Clackamas, Eastport, Mill Plain, Cornelius, Pioneer Place, Bridgeport, City Center, Division, Evergreen Parkway, Fox Tower, Hilltop, Movies On TV, Sherwood, Tigard, Wilsonville, Sandy.