FILTHY, FUNNY and sweet in equal measure, "The 40-Year-Old Virgin" has a lot more going for it than its thin premise -- embodied in the says-it-all title -- would suggest. In other words, there's something deeper, or at least slightly different than you might expect, at play than the efforts of its hero, late-bloomer Andy Stitzer (Steve Carell), to be deflowered.

In fact, the movie is less about Andy's quest for the Holy Grail of intercourse than it is about his half-hearted, perhaps even perverse, mission to stay celibate. This despite the energetic machinations of his well-meaning work pals (Paul Rudd, Romany Malco and Seth Rogen), who take it upon themselves to school Andy in the ways of love, and the unexpected appearance of a compliant and attractive partner (Catherine Keener). In short, it isn't the story of a man who desperately wants to get some, but of a man who kind of, sort of doesn't.

What on Earth is wrong with him?

Not much, it turns out. Not as played by Carell, in whose action-figure-obsessed electronics-store clerk we keep looking for signs of emotional or psychological damage: "I thought you were a serial killer," Andy's co-worker Cal (Rogen) confesses after he discovers exactly what's "different" about Andy. In the end, all we ever find in Carell's brilliantly loopy yet solidly grounded character is a regular, if slightly rusty, Romeo. That's right. All kidding aside (and the movie is a raunchy joke-fest), "The 40-Year-Old Virgin" is, at heart, a love story, albeit one whose hilarious consummation, featuring a musical dance number choreographed to "Aquarius/Let the Sun Shine In," has as much to do with Andy's long-delayed physical release as with his finding a soul mate. It's a chick flick with a lot of really, really dirty jokes -- not to mention a scene that has permanently altered the mental image that will henceforth come to mind whenever I hear Lionel Ritchie's "Hello," and not in a good way.

There is, as you might expect, much that I can't even begin to describe in a family newspaper, starting with the opening shot of Andy in obvious sexual arousal. Based on a character the actor developed years ago for the improvisational comedy troupe Second City, the feature directorial debut of comedian-turned-writer/producer Judd "Freaks and Geeks" Apatow (who co-wrote the script with Carell, ) is a symphony with blue humor. Comic riffs involving condoms, breasts, oral sex, masturbation, sexual climax and the sheer mechanics of doin' it -- or, as in Andy's case, not doin' it -- abound.

What I can describe, although you may not want me to, is one very funny, though painful, scene involving Andy's decision to have his chest waxed. (The actor actually submitted to the procedure.) As real blood pools on Carell's chest after the third or fourth swipe, you may find yourself, as Rudd, Malco and Rogen do, alternating between laughing and wincing. Another classic moment involves Andy's very drunk (and very, er, available) date throwing up a seafood sandwich on our hero's face, even as she's propositioning him.

Like "American Pie" and "There's Something About Mary," the movie can stoop pretty low at times. What keeps "The 40-Year-Old Virgin" out of Rob Schneider territory, however, is: 1) the fact that it's pretty darn funny, and in a way that feels consistently real, and 2) the fact that it's actually an excellent date movie.

It would be all too easy to portray Andy as a freak or Keener's kooky but good-hearted love interest as the kind of implausible dream girl that losers manage to hook up with only in Hollywood fantasies. Both actors, nevertheless, succeed in making their characters' attraction seem not just cinematically sound, but sane.

Paradoxically, the movie's real accomplishment, particularly in this indulgence-saturated society, is in its depiction of celibacy -- or at least saving it for the right one -- which here seems almost less silly than sex.

THE 40-YEAR-OLD VIRGIN (R, 111 minutes) -- Contains raunchy sex humor, drug use, obscenity, partial nudity and glimpses of a porn film. Area theaters.

Andy (Steve Carell) submits to an actual chest-waxing in "The 40-Year-Old Virgin" as his pals David (Paul Rudd), left, and Cal (Seth Rogen) recoil in horror.