If big screen comedy has an assigned savior, it just might be Judd Apatow. With the beloved 40 Year Old Virgin fresh in everyone’s minds, and his producer’s imprint on other humor hits like Anchorman: The Legend of Ron Burgundy and Talladega Nights: The Ballad of Ricky Bobby, this is one comic genius who is definitely on a roll. Need further proof? Well, look no further than his most recent masterpiece of mirth Knocked Up. Not only is it the funniest film in decades, but its easily one of 2007’s best efforts. It’s hilarious, heartfelt, endearing and just a wee bit evil in how it depicts the rigors of adult responsibility, and the inherent human desire to shirk same. Instead of presenting the standard Hollywood party line about biology being the balm for all individual issues, Apatow shows procreation for what it really is—a physical act that leads to seismic psychological shifts.

The interpersonal earthquake here occurs when E! Entertainment producer Alison Scott (an amazing Katherine Heigl) learns she’s been picked to be an on-air personality. Desperate to celebrate the promotion, she gets her married sister Debbie (Leslie Mann) to join her for a night of drinks and dancing at a local hot spot. There, Alison meets the bumbling Ben Stone (a brilliant Seth Rogen). Endearing in a shaggy dog sort of way, he’s a wannabe Internet entrepreneur who hopes to start a website database of famous film nude scenes. The two take an alcohol fueled liking to each other, and after a protection free one night stand, the pair have a potential pregnancy to deal with. Support is shaky from both sides. Alison’s family fluctuates between flabbergasted and favorable. Ben’s bevy of slacker roommates can only think in terms of sexual conquests and scoring.

It requires someone of substantial cinematic ability to balance this clever career girl catastrophe with the Beavis and Butthead viewpoint of Ben’s buddies, but Apatow manages remarkably well. The movie never misses a beat and finds infinitely imaginative ways to brilliantly highlight both the sacred and profane. Unlike other R rated efforts that trade gratuity for genuine wit, Knocked Up is crude, obscene, crass…and utterly charming. Apatow’s characters talk like real people talk, including all the off color craziness and foul mouthed philosophizing that comes with hanging out. Thanks to some equally inventive running jokes (Ben’s friend Martin finds himself the butt of dozens of hirsute-oriented slams when he decides to grow his hair for a bet) and a unique knowledge of when and where to push the gross out gags (always right to the edge of repugnancy), the comedy covers all aspects of the genre.

But there is more to what Apatow is doing than simply larding on the laughs. His moviemaking ideal is a throwback to the days when people, not plotpoints, drove the delirium dynamic. It’s nothing overly complicated. In fact, his secret is something very simple—he lets the characters play out organically, developing along legitimate logistical lines while occasionally tweaking the situational elements to accent their advancement. By the end, we are not only invested in the individuals suffering at the center of the narrative, but we can’t wait to see how the ancillary players pull their weight and supplement the story. When done right, the result is something entertaining and engaging. In Apatow’s case, his accomplishment far exceeds expectations. What he delivers is something close to definitive.

Of course, his actors help out tremendously. Rogen, a longtime comic collaborator, is the perfect sad sack hero. He’s not solidly self-deprecating, nor is he cravenly cocky. He exists right in the middle of both emotional extremes, and when you add in his solid sense of sarcasm, he becomes someone we can instantly identify with. Heigl, on the other hand, has the much harder role. She has to play TV personality perkiness without becoming an irritating shrew, and the moments where she has to act selfish and superior never come across as harsh or horrible. Of course, this couple will have more than its fair share of ups and downs – compatibility is not high on their initial meet-cute conceit. But as they grow, as Apatow allows them to flower and fail, we find ourselves lost in their developing love story. Soon, all we care about is how destiny will determine the pair’s possibilities. The penis and vagina jokes are just a wondrous addition to the emotional mix.

By contrast, Leslie Mann (Apatow’s real life wife) and Paul Rudd (as Debbie’s beleaguered husband Pete) are a fascinating study of responsibility ruining an individual’s hope and compassion. With two precocious daughters determining their every move, the film appears to be setting them up as the cautionary example to guide Alison and Ben. We are supposed to see how marriage and maturity undermine one’s personality to create a kind of composite shell of one’s former self. But Apatow adds layers that indicate something much stronger than that. Indeed, Knocked Up‘s entire raison d’etra appears to be acknowledging that the arriving adventures in child rearing can be just as life affirming as the old habits we so desperately hold onto. But he’s clear to show that there’s no bed of roses at the end of the reproductive rainbow.

Thanks to a remarkable ensemble made up of pals from Apatow’s Freaks and Geeks days (Jason Segel, Martin Starr), a few freaky star turns (Ryan Seacrest and Spider-Man‘s James Franco are wonderful) and some surprising cameos (SCTV’s Harold Ramis as Ben’s dad, Joanna Kerns as Alison’s mom), Knocked Up becomes a surprise a minute sensation, a film that never lets on where it’s going next, or how it will foster its next line of laughter. Make no mistake about it – this is one incredibly funny film, the kind of gasping for air joviality that hasn’t been seen since Trey Parker and Matt Stone delivered their manic musical South Park movie.  In an era when the big screen comedy has been reduced to either an exercise in insular irony or bad taste level ludicrousness, it’s refreshing to find a film that actually earns every second of side splitting splendor.

It is clear that, come December, Knocked Up will remain a member of 2007’s hit hierarchy. If it doesn’t become a big time blockbuster, earning ample accolades on top of its barrelful of greenbacks, there is something wrong with the post-millennial movie going public. Reaching across demographic designs to endear itself to oldsters and adolescents alike, and achieving that legitimate rarity in rib-tickling—that is, comedy that actually has something profound to say about the human condition—this is what pure popcorn entertainment is all about. Hollywood should scuttle its subjective sequels and ridiculous remakes and study Apatow for his take on things. Cinema would definitely be a more joyful artform because of it.

—Bill Gibron