FAILURE TO LAUNCH

(three and a half stars)

Sex and the slacker.

Running time: 97 minutes. Rated PG-13 (profanity, sexual content, partial nudity).

At the E-Walk, the Lincoln Square, Kips Bay, others.

HERE’S what was missing from “Sex and the City”: paintball war, video games and a homicidal chipmunk. “Failure to Launch” has it all, plus Terry Bradshaw instead of Carrie Bradshaw.

For “Sex and the City” fans wondering who this other Bradshaw is: That’s the point. This is a guy comedy being mismarketed as a chick flick, complete with a poster that looks like a page from Lucky magazine.

Matthew McConaughey plays Tripp, a 35-year-old sailboat salesman who drives a Porsche and dates hot women. Also, he lives with his parents. Going in, I thought: McC is 10 years too old to pull this off. I was wrong. The man will still be the sultan of slack at 60. When they come to install his pacemaker, they’ll find him playing the bongos naked.

Tripp’s parents (Bradshaw and Kathy Bates) secretly hire Paula (Sarah Jessica Parker), a sort of guidance counselor for unweaned men, to get him to fall in love with her and move out of the house.

Tripp is in no hurry to grow up; his rock-climbing buddies, he points out, think he’s pretty cool. They live with their parents. Still, he and Paula start to click, and she starts to feel guilty she’s getting paid.

Thanks to zippy direction by Tom Dey and a zingy script by sitcom guys Tom J. Astle and Matt Ember, this is McConaughey’s best movie since “How to Lose a Guy in 10 Days,” which had virtually the same story line but lacked the cheerful dementia that keeps “Failure” fresh and funny throughout.

Paula’s roommate, for instance, instead of being the stock best friend with the pajamas and the chamomile tea, guzzles cheap beer and gets enraged by the mockingbird outside her window (“What the hell kind of devil bird chirps at night?”). She’s played by Zooey Deschanel, oozing weapons-grade sarcasm. The character is like the offspring of Catherine Keener and Carl the groundskeeper from “Caddyshack.” Deschanel turns a throwaway scene, in which she resolves to shoot the tweety bird next door, into the funniest one in the movie.

Parker looks great and puts across both physical comedy (she gets into playing paintball with Tripp, telling him when he’s eliminated, “You will not have died in vain”) and dialogue that’s always about 45 degrees stranger than you expect. Forced to pretend to be a boat buyer, she looks at one vessel and chirps, “She certainly is yar!” Her “Sex and the City” scripts often seemed like they’d been artificially injected with puns by some BALCO of comedy, but this one pulls off the more difficult trick of sounding improvised. Even some overheard lines are brilliant: “Guys who drink Kahlua and cream are not power guys!”

All the supporting actors get lots of laughs, too, particularly Bradshaw, the former ball-tosser for the Pittsburgh Steelers who hasn’t been seen on the big screen since “Cannonball Run.” He’s a natural as the goofy dad who yearns for a “naked room” where he can let his pigskin hang out.

Nothing much makes sense: 40-year-old SJP rooming with Deschanel, 26? And if the parents want Tripp out, why do they make him breakfast and do his laundry? But it all helps make what could have been a rote romantic comedy appealingly weird.

kyle.smith@nypost.com