'OH' is a singular success for Posey

If the news that Parker Posey plays a perky yuppie looking for her first orgasm in ``The OH in Ohio" sounds too good to be true, it's not. The role of Priscilla Chase, a sexually closed off workaholic who learns to love herself , is the best yet in Posey's uniquely funny, highly original body of work. Calling what she does here a career performance makes it seem, wrongly, like the sort of pull-out-the-stops, capital-A acting that wins Oscars, though I'd certainly give her one for this movie.

It's a thrill to watch Posey incorporate, at last, some true emotion into her exuberant screwball wit. The neurotic pranks of ``Party Girl," ``The House of Yes," and ``Henry Fool" have deepened into a more, dare I say, mature approach to madcap anxiety. Aside from her gentle segment in Rebecca Miller's ``Personal Velocity," this is a rare occasion where Posey seems approachably human.

But ``The OH in Ohio" is a much better movie than Miller's. Wonderfully written by Adam Wierzbianski and directed by Billy Kent, the film recalls a couple of Paul Mazursky's astute sex comedies from the 1970s (``Blume in Love" and ``An Unmarried Woman").

Like those pictures, ``Ohio" is actually the story of a marriage on its last leg. Priscilla and Jake (Paul Rudd) have been together for years. But their lives are on different tracks. She's just been promoted to a vice president's post at her marketing firm (predictability being her most prized asset). He's been teaching science at a Cleveland public high school. She's elated. He's bitterly depressed.

As it happens, he's miserable over the quality of the sex they have. And one night at home, as she tries to celebrate her promotion with him, he complains with a frankness that borders on the Updikean. ``Do you have any idea what your frigidity has done to me?" he begins. She confesses that he's never given her an orgasm. Subsequent attempts to correct that prove fruitless. He turns hostile, and, hurt, she banishes him to the garage, where he sulks and pouts.

From here, the film blooms quite sensitively into a dual quest for fulfillment. Jack thinks he might have found it with one of his brainy students (Mischa Barton, surprisingly sweet). Priscilla has a more unruly time locating the source of her sexual dysfunction and its cure. She tries group therapy with Liza Minnelli, in a ludicrous cameo as a gyno-guru. Minnelli leads a class in women helping themselves, which, amazingly, Priscilla never has done.

Fifty million people suffer from sexual dysfunction, Minnelli says with that legendary slur. ``But tonight that number will drop by 10!" Nine, actually. Minnelli tries to get Priscilla to hold a mirror to her private parts, but in an absurdly touching struggle, she can't. Even the swimming pool Priscilla doesn't want installed becomes an extension of her self-denial. (Danny DeVito plays the pool guy, and this is the first film to make clear what more than 35 years of TV and movies could not: He's kind of sexy.)

Priscilla's sassy co-worker friend (Miranda Bailey) offers her advice. But Priscilla quickly discovers it's the friend with batteries that changes her life. If the sight of an embarrassed Posey purchasing a vibrator is amusing, the numerous scenes and sequences of her using it are uproarious. She makes up for the ``482" times nothing ever happened with Jack and spirals, naturally, into addiction.

As terrific as Posey is in these passages, ``The OH in Ohio" is not a one-joke comedy. The farcical tone in Priscilla's sexual over-liberation melts away and the movie's sincerity sets in. Her ecstasy is tempered with the sad awareness that no man (or woman) can make her feel as good as her machine does.

Through all the lewd gags, the filmmakers insist that we see, feel, and root for Priscilla's bliss. Posey makes it impossible to do otherwise. This is one of the sweetest, smartest sex comedies I've ever seen, in part because the sex, both for Priscilla and Jack, is not an end. It's a means to real self-understanding.

The 1970s version of this movie would have ended in psychotherapy, death, or both. This one ends with Posey flipping like a dolphin in a pool. She's not having an orgasm. Nonetheless, she makes you want to jump in and have whatever she's having.

Wesley Morris can be reached at wmorris@globe.com.