(CNN) -- The new film from producer Judd Apatow and "Forgetting Sarah Marshall" director Nicholas Stoller is a raunchy, raucously funny rock 'n' roll comedy.
British comedian Russell Brand plays rock god Aldous Snow, an infinitesimal variation on the sexy narcissist from "Sarah Marshall" (he vaguely remembers sleeping with her, too). Aldous is the love child of Mick Jagger and Keith Richards, a thin-skinned hedonist fallen on hard times after his album "African Child" (a priceless rip on Michael Jackson's "Earth Song") has been universally savaged as the worst thing to hit that continent since war and famine.
Still, he's been languishing in the has-been bin for too long. With the 10th anniversary of his greatest gig looming, low-ranking record executive Aaron Green (Jonah Hill) is dispatched to London to escort his hero back to the Greek Theatre in Los Angeles for a multimillion-dollar comeback concert.
The only serious obstacle in this seemingly quick-n-easy quest is Aldous, who hasn't just fallen off the wagon; he's loaded it up with booze (absinthe), drugs (don't ask) and any woman who catches his eye. Aaron can only try to keep up.
With its hard R language and red-band sex, the movie is every bit as excessive as rock 'n' roll used to be, the satire the music industry undoubtedly deserves. It also presents something of a challenge to mainstream movie reviewers, who are supposed to exhibit a sense of decorum that seems quaint confronted with today's taboo-busting comedies.
In what is significantly more than a cameo, Sean Combs is the desperately pragmatic record label boss, Sergio, whose unprintable advice -- and withering glare -- keeps Aaron hopping. In one hallucinogenic scene, a disembodied Combs eats his own head, which is actually less disturbing than it sounds.
Funnier than Apatow's "Funny People" (another semi-appalled, semi-fascinated glimpse into the VIP room of celebrity culture) and by some margin the best showcase yet for Jonah Hill's buggy wit, "Get Him to the Greek" has the same drug-fueled, binge-and-evacuate mentality as "The Hangover," climaxing in a hysterically ugly stopover in Las Vegas involving guns, knives, groupies, furry walls and a cocktail of narcotics.
That's the farcical climax but not the end of the story, which keeps plugging away for another 20 minutes to put its finger on the mandatory redemptive life lesson for Aaron and his girl (Elisabeth Moss, from "Mad Men").
Stoller (who also wrote the screenplay based on characters by Jason Segel) has no knack for transitions or character development. More than once, it seems to just pass out, but it's been resuscitated in the editing.
To his credit, Stoller keeps looking for the edge, but whenever he finds it, he backs off sharply, as if all that sex and drugs are an impediment to rock 'n' roll and not its core being. Scenes supposed to fill in the emotional void behind Brand's numb party antics are hit-and-miss at best, though he's genuinely endearing in a phone conversation with his ex (Rose Byrne).
Luckily, there's real chemistry between the two stars, who egg each other on toward behavioral lows that are often enough comic highs. It's not always pretty, but this is the funniest on release right now.