Everything about ?Failure to Launch? screams out ?typical romantic comedy,? from the cutesy title to the whimsical posters (featuring stars Matthew McConaughey and Sarah Jessica Parker and their blindingly white teeth) to the absurdly contrived premise.

McConaughey plays a 35-year-old boat salesman who still lives at home with his parents and has no interest in moving out. Appropriately, his character?s name is Tripp (that?s right, with two P?s) and the role is a perfect fit for McConaughey?s signature brand of smug, good-ole-boy uselessness.

Tripp?s parents (played by Kathy Bates and Terry Bradshaw with such endearing goofiness, who?d want to leave them?) hire Parker?s character, a life interventionist named Paula, to make him fall for her and inspire him to leave the nest. Which technically makes her a prostitute, but whatever. Semantics.

You know from the start that there will be the great deception, followed by unexpected love, followed by discovery of the great deception, followed by an over-the-top reconciliation. Usually within the genre, that last step takes place at the airport, or on the way to the airport, as was the case in ?How to Lose a Guy in 10 Days.? Which also starred ? that?s right ? Matthew McConaughey.

He and Parker both are essentially playing versions of the personae they?ve carved out for themselves time and time again. She?s perky and verbal and hyperanalytical like Carrie Bradshaw on ?Sex and the City.? (?Failure to Launch? could have been a title of an episode of that show; you could easily imagine Charlotte falling for a guy who still lives at home with his parents, with the other three women urging her over salads to dump him.) He?s smooth and cocky and laid-back, just as he?s been in every other film with the exception of ?A Time to Kill. Director Tom Dey (?Shanghai Noon,? ?Showtime?), working from the first produced screenplay by longtime TV sitcom writers Tom J. Astle and Matt Ember, ups the wacky factor with intrusively jaunty music, overgrown adolescent activities like paintball and a running gag in which Tripp gets bitten by a series of angry animals. It isn?t terribly funny the first time.

And yet there are elements of ?Failure to Launch? that elevate it, albeit sporadically, above the typical romantic comedy that it is. It has a great supporting cast ? besides Bates and Bradshaw, there?s Zooey Deschanel, always a scene-stealer, as Paula?s sarcastic roommate.

And the characters are meatier and better drawn than you might expect.

Deschanel?s character, Kit, is a functioning alcoholic; it?s played for laughs but she actually has a serious drinking problem. And Bates has a surprisingly touching scene in which her character wonders whether Tripp?s dad will still love her once he gets to know her again, one on one, without their son around as a buffer.

Bates adds substance simply by showing up, and almost redeems matters ? until Tripp goes rock climbing with his buddies and gets bitten by some sort of vegetarian Gila monster.

?Failure to Launch,? a Paramount Pictures release, is rated PG-13 for sexual content, partial nudity and language. Running time: 97 minutes. Two stars out of four.