KNOCKED UP — *** 1/2 — Katherine Heigl, Seth Rogen, Paul Rudd; rated R (vulgarity, profanity, sex, drugs, nudity, violence, slurs).

In terms of offensive sexual content , "Knocked Up" is one of the more crude and crass films scheduled for this summer. A romantic comedy obsessed with sexual humor and drug gags, this one makes the Farrelly brothers' films look tame by comparison.

But "Knocked Up" also has more heart than any of the Hollywood blockbusters released so far this year ... combined. And for those who aren't easily offended, there are many laugh-out-loud sequences and a moist-eyed finale that provides a redemptive moment of sorts.

"Knocked Up" is an attempt to mine the same "salty-yet-sweet" formula that worked for "The 40-Year-Old Virgin." The same filmmaker, Judd Apatow, and many of the cast members return here, including Seth Rogen — an uncredited contributor to the screenplay, who also stars here.

Rogan plays Ben Stone, who recently had a one-night stand with entertainment television producer Alison Scott (Katherine Heigl). Alison was out celebrating a TV promotion to on-air talent, and a month later she discovers she's pregnant. She has decided to keep the child, but she isn't sure she wants a relationship with Ben.

After all, he has no real job — outside of running a questionable Web site with his drug-addled buddies (Jason Segel, Jonah Hill, Jay Baruchel and Martin Starr). And besides, he doesn't exactly look like he's thrilled by this turn of events.

Rogen — who's had supporting roles in films and such television shows as Apatow's "Freaks and Geeks" and "Undeclared" — proves he's got legitimate big-screen presence. A bigger surprise is his believable chemistry with Heigl (TV's "Grey's Anatomy"). Together, they're an appealing onscreen couple, and we really grow to care about these two characters.

Their co-stars — who include Apatow regular Paul Rudd and Apatow's wife Leslie Mann — are terrific. Current "Saturday Night Live" cast member Kristen Wiig is also hilarious as Alison's sarcastic co-worker. Even "American Idol" host Ryan Seacrest is amusing in a cameo poking fun at himself, as well as superficial Hollywood stars.

"Knocked Up" is rated R for crude sexual humor and language (profanity, slang terms and other explicit talk), some other questionable comic bits (scatological jokes and references), simulated sex and other sexual content, strong drug content (marijuana use and references, as well as other hallucinogens), male and female nudity, comic violence, and some slurs based on ethnicity and sexual preference. Running time: 125 minutes.

---

E-mail: jeff@desnews.com