It’s hard to be authentic about high school’s angst, peer pressure and idiotic behavior years removed from the experience.

Perhaps pals Seth Rogen and Evan Goldberg knew that when they started a script for Superbad at 14. More likely, they just giggled over a character strangely compelled to draw penises as a child.

Adult perspective can torpedo teen comedies into a sea of stereotypes, as writers compile into predictable groups what they can no longer specifically recall. Remarkably, Goldberg (who wrote for Da Ali G Show) and Rogen (a bonafide comedy star after Knocked Up) avoid the trap. Their script is actually better now that they’re adults. Like its great predecessors, Superbad knows that the anxieties don’t end after the teenage turning point in life, they mutate over the next 30 years.

Stamped with producer Judd Apatow’s irresistible blend of filth and feeling, Superbad is as knowingly bittersweet as it is hilariously profane and frankly sexual. (Unlike Knocked Up, which Apatow wrote and directed, it also doesn’t overstay its welcome.)

There’s the notebook gag, along with a bodily function joke far grosser than it initially seems. But longtime indie-film director Greg Mottola never gratuitously lingers for the ick factor. As are Rogen and Goldberg, he’s more interested in direct talk about loyalty, loneliness and frustrations.

To that end, it’s packed with riotous kicks and intelligent, witty choices. The girls pursued aren’t unattainable for overweight or schlubby guys. Its funk-soul soundtrack is the sort that plays in every man’s brain at least once in his life when making a play. Since subject matter isn’t era-specific, certain details zig and zag (cell phones, four-ink pens, the ’70s Columbia Pictures logo).

Still, this bro-mantic comedy wouldn’t be the same without star-making turns from Jonah Hill and Michael Cera as Seth and Evan, lifelong pals nearing the end of senior year. Evan’s headed to college. Seth is headed nowhere. Seth has long-ago sexual experience (“I peaked too early,” he laments). Evan hasn’t gotten out of the batter’s box with his crush, Becca (Martha MacIsaac).

Another night of shotgunned beers and basement Web porn awaits, until Jules (Emma Stone) — for whom Seth has a thing — enlists Seth to get alcohol for her party. Enter Fogell (Christopher Mintz-Plasse), the duo’s even-dorkier third wheel, who has a fake ID. (You’ll forever remember Fogell’s bogus name, McLovin, and newcomer Mintz-Plasse’s authentic performance. He blossoms from an easy squeaky-voiced punchline into the only truly self-confident amigo around.)

After Fogell survives a convenience-store robbery, he’s taken on a rowdy ride-along by two oddball cops (Rogen and Saturday Night Live‘s Bill Hader.) Left to their own devices, Seth and Evan deal with a series of wild events that endanger their chances for sex and continued friendship.

Less rigid but equally uptight as his George Michael on TV’s Arrested Development, Cera’s lovable droopy-dog anxiousness makes him a perfect sweaty-palmed straight man. Hill uses the F-bomb like a hiccup he can’t control, constantly computing coital odds as circumstances change. There’s a reason Hill wears a Richard Pryor T-shirt; his bawdy-sweet sensibility is much the same.

Overtly, it’s a man show. However, there’s a wise, subtle suggestion that Becca and Jules have had their own unseen, nightlong adventure of nervous expectations, if not outrageous setbacks. (In particular, MacIsaac has a late scene that’s simultaneously awkward, aggressive, funny and sad.)

The reassuring message of 2007’s new funniest film so far (after Knocked Up) is there’s no prefab, encompassing approach to life — just the hope that stumbled-upon strengths point in the right direction. On the way, barking at the moon can be a great temporary defense mechanism.