Like director Judd Apatow's last movie, "The 40 Year-Old Virgin," his new one, "Knocked Up," is a pungent stew of filthy guy-talk, gross-out sight gags and pure, un-ironic romance. And like "Virgin" — which perfected this tricky chick-flick/guy-flick cross-pollination — it's a deliriously, paralyzingly ... well, no need to oversell it: Let's just say it's a very funny movie.

The setup: Underachieving pothead Ben (the frankly tubby Seth Rogen) meets on-the-rise TV professional Alison (the blatantly beautiful Katherine Heigl) at a bar, where she's celebrating her promotion from behind-the-scenes producer to on-air personality at E! News. Although they couldn't be more unalike in every obvious way, Alison thinks Ben is sweet. So they drink, dance, drink, drink, and go back to her place and have sex. Not a lot of sweet talk ensues ("I'm sorry I'm sweating on you," he says, from his missionary POV); and due to an unfortunate misunderstanding on Ben's part, no condom is involved, either. The next morning, Alison woozily awakes to the sight of Ben's bare, doughy butt peeking out from the sheets and realizes that there are worse things in life than, say, death. Especially after Ben arises and regales her with his backstory and current biographical details. First of all, he has no job. However, he and his four equally overbaked roommates are engaged, in between bong hits and beer-gargling, in setting up their own nudie Web site: "Flesh of the Stars." Alison politely flees.

A few weeks later, in the middle of an E! celebrity interview with James Franco (like several other cast members, a veteran of Apatow's cult TV series, "Freaks and Geeks"), Alison suddenly has to dash off-camera to throw up in a bucket. After a desperate test-drive through an array of home pregnancy kits (a scene that can only be described as deliriously and paralyzingly funny), Alison realizes that she is, in fact, pregnant. I can imagine some dark female muttering around about here, because when Alison informs Ben that not only is she expecting, but that she's going to keep the baby, Ben, whose only experience of responsibility heretofore has been trying not to hog the bong, announces that he's going to stay by her side and help raise the child. He and Alison are both in their mid-20s. They barely know each other. Yet there's no thought of terminating her pregnancy. How often might this sort of thing happen?

Who cares? The movie is a romantic fantasy. It's not a mindless one, though. Apatow casts a hopeful eye on the human capacity for love and commitment, even in the most unexpected quarters; and he gives sympathetic consideration to both the difficulty and the necessity of growing up. But these are grace notes. Mainly, from beginning to end, "Knocked Up" is a carnival of character-driven hilarity — priceless scenes tumble forth like endless clowns out of a tiny car. Seth Rogen and Katherine Heigl, who each take giant steps toward stardom in this movie, are an unlikely yet perfect match. His boundless amiability and superb, throwaway delivery are a complete pleasure. (When Alison asks, with innocent shiksa curiosity, what he uses on his cute curly hair, Ben half-mumbles, "I use ... Jew, it's called.") And Heigl does an end run around her radiant blondeness to demonstrate solid comic responses to the most appalling varieties of male meatballism. (You have to see her face during a visit to the family gynecologist, when the smarmy doctor peers beneath the sheet and wisecracks, "You really do look like your sister.")

Positioned against Ben's überslob buddies (Jason Segel, Jay Baruchel, Jonah Hill and Martin Starr, all delectably unevolved in different ways) are Alison's older sibling, Debbie (Leslie Mann, a "Virgin" veteran), and her husband, Pete (Paul Rudd, likewise), who appear to be the very incarnation of marital contentment. But Debbie has begun to mourn her fading youth. (The scene in which she and Alison are turned away from a trendy nightclub on grounds of insufficient hotness is a perfectly constructed comic eruption.) And secretly-wretched Pete misses the guy-guy camaraderie of which he feels domestic bliss has robbed him. (Even the couple's two cute kids can't dispel his gloom: "Their smiling faces just point out your inability to enjoy anything," he says dismally.) Pete finally breaks free by whisking Ben off on a spur-of-the-moment road trip to Las Vegas to see Cirque du Soleil — unwisely taking along a bag of 'shrooms to heighten the experience. (This — believe it — is one of the movie's most hysterical sequences.)

Apatow's script is so filled with dazzling comedic wordplay that even the minor characters get to deploy some. A gibbering, pot-swozzled girlfriend played by Charlyne Yi could be spun off into her own TV series; and Craig Robinson, as the imposing keeper of the nightclub's velvet rope, has a quick, concentrated monologue that blends sorrow, anger and unanticipated warmth in perfectly measured proportions. Maybe best of all, actual E! News star Ryan Seacrest does a gleeful turn playing himself as an ego-stuffed idiot, and going off on Jessica Simpson in a way that may come back to make his day job difficult.

"Knocked Up" has an elegance of form, a generosity of spirit and a mad determination to take things too far — and then farther — that approaches comic perfection. And then actually achieves it.

"Day Watch": Dark City

The Russian director Timur Bekmambetov is clearly onto something, and he's onto an awful lot of it. His new movie, "Day Watch," the exhaustingly baroque sequel to his 2004 "Night Watch," which was released here last year, continues the saga of the forces of Light and Darkness — wizards, vampires, witches, what have you — suspiciously circling each other in modern-day Moscow. My head hurts at the thought of running down this movie's plot, but here goes:

As we learned in the last film, the forces of, again, Light and Darkness have been kept from each other's throats by a thousand-year-old truce, which is enforced by roving patrols of the Night Watch (keeping an eye on the bad guys) and the Day Watch (bad guys eyeing them right back). In the new movie, we learn that the truce may be about to collapse. A boy named Egor (smoldery Dima Martynov) — a Great Other, as they say in these circles — has gone over to the Dark side. But then a young woman named Svetlana (pretty Mariya Poroshina) has emerged as a Great Other on the side of the Light. Svetlana is currently a trainee under the Night Watch officer Anton (disheveled hipster Konstantin Khabensky), who happens also to be the father of Egor. Meanwhile, the head Dark guy, Zavulon (shameless hambone Viktor Verzhbitsky), is plotting to frame Anton for murder, thus trashing the truce and bringing on the end of ... everything, I guess.

Can Zavulon's scheme be foiled? Yes — by the Chalk of Fate! This ancient whatchamacallit was last seen clutched tight in the dead hand of the 14th Century conqueror Tamerlane when he was buried in the fabled city of Samarkand. Or so somebody thought back then, anyway. Anton decides he must journey to Samarkand and retrieve the Chalk. And he does, sort of. I say sort of, because before he goes anywhere, he is ordered by his Night Watch boss to trade bodies with a female colleague named Olga (tough girl Galina Tyunina) — a one-time Great Other who was "stripped of her powers." So Olga and Anton switch bodies, allowing Olga (actually Anton now) to say things like, "Why is my ass wiggling?" and Anton (now Olga) to reply, "Because it's mine." Got it? Doesn't matter. Anton sets off for Samarkand, looking for all the world like Olga, leaving his body behind, chock full of Olga, to face Zavulon's devious machinations.

Enough. Director Bekmambetov, inevitably a veteran of television commercials and music videos, is in thrall to American action movies, especially of the more ornate variety (think Ridley Scott, James Cameron, the Wachowskis). He once actually made a film with cheese genius Roger Corman, who taught him how to get maximum bang for every precious production buck. So there's plenty of bang here — the flashback chaos of a Tamerlane invasion, a torn-loose Ferris wheel careening through the streets, a head-on collision (this is really good) in which one car comes barreling out the backside of another. But there's also considerable cheese. The subtitles are animated, for one thing — they slip, slide and wriggle in a way that would have to qualify as daffy in any language. And the Moscow interiors are unrelentingly drab — even the formidable Zavulon appears to be headquartered in an abandoned ballroom. (I realize this sort of thing may resonate differently in Russia, but after a while I didn't care.)

"Day Watch" looks huge — Bekmambetov really knows how to marshal his limited resources. But the picture feels heavy; sitting through it is like swimming through lard. Since both this film and its predecessor set box-office records in Russia, I suspect that some important cultural component is being lost in translation. Maybe, like cobra-blood cocktails, or haggis, it just won't travel. But I wish the director well — he's not a simple hack — and I gather the concluding installment of this story, called "Dusk Watch," is even now in the works. Good luck and all. No rush, though.

Check out everything we've got on "Knocked Up" and "Daywatch".

Visit Movies on MTV.com for more from Hollywood, including news, reviews, interviews and more.

For breaking news, celebrity columns, humor and more — updated around the clock — visit MTVMoviesBlog.com.

Want trailers? Visit the Trailer Park for the newest, scariest and funniest coming attractions anywhere.