'No Hard Feelings' review: Jennifer Lawrence is the only reason to see film

"No Hard Feelings" hits theaters shooting for the lowest bar. Mission accomplished since it's a crude sex farce about a thirtyish woman who seduces a teen boy in exchange for a Buick.

But wait. It must be more than that. How else would Oscar winner Jennifer Lawrence—Katniss in "Hunger Games" for Pete's sake— be persuaded to say, "this one's for me" and then agree to going full frontal on a beach while fighting high school kids who stole her clothes.

I'll tell you how. At its core, the R-rated "No Hard Feelings" is only playing at being dirty. Behind the carnal jokes lurks a Hallmark heart. Lawrence's formula movie is only fitfully watchable, but she can spin comic zingers like nobody's business and her frisky charm is irresistible.

It better be. Back in the day of Mrs. Robinson ("The Graduate") and Stifler's mom ("American Pie"), cougars were easy to play for laughs. But in this era of harassment policing, some viewers may want to call child protective services. Imagine the outrage today if a male star signed on to play a dude taking a payout to have sex with a virginal teen girl. The mind boggles.

"No Hard Feelings" has more problems than bad timing. Start with the script that director Gene Stupnitsky ("Good Boys") wrote with John Phillips, who gave us the immortally awful "Dirty Grandpa," a career nadir for another Oscar winner, Robert De Niro.

The story asks us to believe that Lawrence's character, Maddie, is desperate. Her salary as a bartender on Long Island's snobby Montauk won't pay the taxes on the house she inherited from her mother. And the car she needs as a summer Uber driver has been repossessed. If you think the filmmakers are tackling income inequality, you're at the wrong movie.

Maddie does answer an ad on Craigslist from a wealthy couple (Matthew Broderick, Laura Benanti) willing to swap their pricey Buick if Maddie can bust their shy, Princeton-bound, sexually inexperienced son Percy (Andrew Barth Feldman) out of his shell. He's 19—that's two years above the consensual limit in New York State.

Will you date him?" the parents ask. "I'll date his brains out," says Maddie, who agrees to keep the deal secret from Percy. Complications ensue when Percy mistakes her offer of a ride home for a kidnapping and he maces her right in the kisser.

. Wait, it gets worse. At a teen party, Percy accidentally punches Maddie in the throat. Then there's that naked moonlight swim when their clothes get stolen. Feldman works wonders with the impossible role of the most naïve teen on the eastern seaboard.

But the film's swerve into schmaltz is harder to swallow. See, Percy and Maddie never went to a prom—aww— so they dress up to visit a posh restaurant, where Percy turns piano boy and sings the hell out of "Maneater" as if he just won Hall and Oates night on American Idol.

Where is this all going? You tell me. Stupnitsky is not without talent—his creative spark is evident in "The Office" and the current gem, "Jury Duty." And it's understandable that Lawrence would want to cut loose after the heavy dramatic lifting of "Causeway" and "Mother."

And cut loose she does. Lawrence is the only reason to see "No Hard Feelings. The rest gets a hard pass.