Well, no actually, you don’t wanna walk straight. You wanna stumble more onto the clever side of the line than the stupid side -- in fact, you wanna walk entirely and purposefully on the clever side, if you can manage it. I was terribly afraid that Walk Hard: The Dewey Cox Story, a sendup of music biopics, wouldn’t manage it, for it comes partly from producer and cowriter Judd Apatow, who has been responsible for some of the most juvenile, most obvious, most predictable and banal attempts at comedy of late: Knocked Up, Superbad, The 40 Year-Old Virgin. Maybe Apatow just needed to get away from sex comedies. Maybe he needed to team up with Jake Kasdan -- his cowriter and director here -- sooner.

Kasdan’s movies have been much smaller but much smarter than Apatow’s: the sweet, snarky tweaking of the television industry in The TV Set, from earlier this year; 1998’s Zero Effect, an off-kilter noir mystery featuring a modern incarnation of Sherlock Holmes. And it’s clear that Kasdan’s sensibilities dominate in Walk Hard, tempering Apatow’s teenage-boy giddiness at getting to goof on such juiciness as illegal drugs and illicit sex and woo-hoo! rock and roll, dude! with a skewering eye that never lets the movie wallow in the base behavior we expect from our rock gods. Instead, it looks awry and with a critical moue at how we celebrate that bad behavior, as well as how we approach pop culture on the whole.

John C. Reilly -- cutting loose like we haven’t quite seen him do before, though his performance in the NASCAR sendup Talladega Nights comes close -- is Dewey Cox, contemporary of Elvis and Buddy Holly, as influential to rock ’n’ roll as the Beatles. We’re familiar with the sad, ironic tale, how Dewey overcame early adversity (family tragedy; a debilitating handicap) to triumph as a world-famous singer and performer (and husband three times over, and father to seemingly countless offspring) before booze and drugs and all that exhausting sex took him down. And then there came his triumphant comeback...

Reilly (A Prairie Home Companion, Dark Water) does all his own singing, by the way -- the tunes are terrific, actually, though the lyrics are snarky -- and he sounds like Roy Orbison, looks like Bob Dylan, and acts like a brilliant madman. And if Walk Hard were nothing but a comic tour de force from one of the most underappreciated actors working today, that would be enough. But there’s a lot more going on. The flick is pulling the legs of flicks including Coal Miner’s Daughter, Ray, and a whole lotta Walk the Line (in fact, I’d venture to guess that the more you adore the deadpan solemnity of Line, the more you’ll get out of this impaling of it). But it isn’t merely aping their clichés and tossing in a fart joke or three: this is a razor-sharp dissection of the new archetype of modern mythology -- the rock star -- and how we interact with him on a societal level... like making worshipful biographical movies about him. It’s deftly cheeky and bursting with a smart appreciation of the entirety of the pop culture of the last half century, but more, too: it’s about us, and what we expect from our heroes, and what we expect from the stories we hear about them.

Which means, too, that the high markers of each of the decades in pop culture from the 50s through to today get a workout: from the iconic hairdos to the changing expressions of fame as mass entertainment evolves (Dewey gets his own variety show in the 70s!). And how Dewey’s real-life compatriots have come to be mere representations of themselves in the public consciousness gets some play too, most notably in what might be the film’s single funniest, can’t-stop-rolling-on-the-floor-laughing scene, when Dewey travels to India to drop acid with the Beatles, who are played by a cadre of today’s most amusing alt-comedy names. I won’t spoil the moment by revealing who plays whom, but the casting is brilliant. Weird, but brilliant.

So put Walk Hard down as one of the great music satires ever made. Well, sure, there’s pretty much only This Is Spinal Tap in that category, but now there’s this one, too, and it is more than worthy to snort some coke backstage with that classic. And I mean that in a metaphoric, archetypal way, of course.

(Technorati tags: Walk Hard, Dewey Cox, John C Reilly, Judd Apatow, Jake Kasdan)