There has been some complaint among Brits about the casting of American Renee Zellweger in the lead role of “Bridget Jones’s Diary,” but a viewing of the adaptation of Helen Fielding’s novel (penned by Fielding, Richard Curtis and Andrew Davies) shows that there’s no basis for the criticism: Zellweger manages the necessary accent as well as Gwyneth Paltrow ever did (and as well as most English performers do when they’re affecting an American speech pattern). The real question is why any actress of either nationality would have wanted the part. The book was apparently very successful, but at least as transferred to the screen, it’s about as prefabricated a romantic comedy as one could imagine–an extended “Cathy” comic strip folded into the old reliable plot (familiar from John Hughes’ high school movies, among hundreds of others) about the rather dim girl who allows herself to be seduced and jilted by an obvious cad while Mr. Right lurks perpetually in the background, all too obvious to everybody but her. The outcome is a foregone conclusion, of course, but there are lots of tears, reversals and assorted quirkiness before we lumber our way to it. Despite the slickness with which it’s been made and Zellweger’s obvious dedication, “Bridget Jones’s Diary” is as a formulaic an excuse for a chick flick as you’re likely to find.

In this incarnation of Plot B-1, Bridget Jones is a slightly overweight and, it must be admitted, pretty dense secretary in a London publishing house. As she tells us in numbingly cute narration, she’s fully aware that her boss Daniel Cleaver (Hugh Grant) is a scoundrel when it comes to women, but in a move that’s close to emotional suicide (undoubtedly brought on by a lack of “self-esteem,” which in this case seems pretty deserved), she allows herself to fall for the guy. Meanwhile she dismisses as a potential beau a scowling human-rights lawyer with an Austenesque name, Mark Darcy (Colin Firth), whom she’s known from childhood, despite the fact that his gloomy attitude all too clearly masks affection for her. The trajectory of the plot is hardly surprising: Bridget has a fling with her boss which turns out badly, she changes jobs to supposedly humorous effect, she links up with the attorney again, Cleaver intervenes one last time, and she eventually opts for Darcy–only to find that he might now be lost to her. Needless to say, he’s not. A picture like this couldn’t exist without a phony happy ending.

As though the central elements weren’t formulaic enough, they’re surrounded by others which are equally so. The heroine has to have eccentric, loquacious chums (here three of them) who pop up periodically to commiserate with her and garner a few cheap laughs. She also has parents going through a bad patch in their marriage–a sharp-tongued mum who goes off with a TV pitchman and becomes his on-air assistant (a completely implausible circumstance), and a quiet, thoughtful dad–as well as the inevitable embarrassing uncle. And she must endure an obligatory succession of humiliating moments–God help us, we even have to watch as, joining klutziness with a lack of culinary skill, she makes a horrendous mess in her kitchen trying desperately to prepare a simple meal! (She winds up, of course, with pots boiling over and blotches of food splattered all over her apron.)

Through it all, Zellweger is an exceptionally good sport. She put on a few pounds for the role, it’s said, and she looks convincingly plump, especially in several extremely unflattering scenes when she has to show an ample amount of flesh (nothing too revealing, of course): a final shot in which she’s standing very scantily-clad in an (obviously computer-generated) snow shower is a case in point. And she squeezes her sweet little face into an agonized grimace as often as required–which, given the twists of the plot, is pretty frequently (though given the quality of the material, perhaps it wasn’t a reaction so hard for her to manage). The feebleness of “Bridget Jones’s Diary” certainly isn’t her fault. Nor is it Hugh Grant’s. He seems to be having a fine time acting the utter rotter; indeed, he’s deliciously slimy even in the inevitable scene in which poor, dopey Bridget finds him with another woman. Firth is like a mobile stick of wood as the good man who pines after Bridget (though why he does so, to be perfectly honest, is hard to fathom); but it’s not his fault the role is a cipher. The supporting players fare even worse. Gemma Jones has to suffer a succession of horrid closeups as Bridget’s mom, while Jim Broadbent is completely wasted as her dad; he has one scene in which, in bringing a cigarette up to his mouth for a puff, his hand bumps into his nose–and the flub wasn’t even reshot. James Callis, Sally Phillips and Shirley Henderson are encouraged to mug and roll their eyes entirely too much as the heroine’s faithful friends. And poor Celia Imrie is reduced to a series of smirks and ticks as Darcy’s partner and supposed intended. Paul Brooke and Felicity Montague are little more than props as offuce colleagues looking on disapprovingly at Bridget’s shenanigans, and Embeth Davidtz has what amounts to a statuesque walk-on as the American girl Cleaver fools around with.

The cast’s difficulties have to be laid mostly at the doorstep of first-time director Sharon Maguire, previously known for her documentaries; she lacks the lightness of touch material of this sort needs if it’s going to have any chance to charm rather than depress. Perhaps the original book, which has become a sort of pop phenomenon, has some quality the adaptation has lost; but a movie has to be taken on its own terms, and as such “Bridget Jones’s Diary” is devoid of the slightest shred of originality or inventiveness, and its tired storyline isn’t enlivened even by the efforts of an able cast. If it weren’t for its British accents, you might confuse it with equally dim American chick flicks like the recent “Someone Like You.” It’s a shaggy-girl story that should have stayed on the printed page.