"Mean Girls"

The Plastics express curiosity about Cady early on, only because she seems like a good target for their cruel scrutiny. (Regina gushingly "admires," with unvarnished disgust, the handmade leather-and-shell bracelet Cady wears.) But Cady amuses and intrigues them, and they decide to initiate her into the fold, but only after they've laid out some very specific rules: On Wednesdays all the Plastics wear pink, and no one must wear a tank top two days in a row. Cady doesn't really want to be a Plastic, but Janis and Damien urge her to infiltrate the group's inner sanctum and report her findings back to them; they hope to sabotage the Plastics by finding out what makes them tick.

That should be simple enough, but then, in high school, nothing is ever simple: Cady falls for the boyfriend Regina has dumped earlier (Jonathan Bennett), not realizing that he's off limits because Regina still considers him her property. Worse yet, Cady drifts all too easily into the rhythm of being a Plastic: The group's power is intoxicating. Worst of all, even though Cady is a good student who's brilliant in math, she dumbs herself down -- refusing, for instance, to join "the Mathletes," an elite group of numbers geeks -- all the better to fit in.

As canny as "Mean Girls" is about the hidden minefields of high-school hierarchies, it's only glancingly homiletic: Cady and her classmates ultimately learn how damaging it is to spread rumors and talk about people behind their backs, but Waters (who directed last year's smart, sprightly "Freaky Friday") and Fey don't deny us the biting pleasure of watching the girls engage in all this nastiness in the first place. "Mean Girls" doesn't turn a blind eye toward the suffering that gossipy girls (or boys) can inflict. But the cruelties inflicted by the Plastics are intelligently stylized: These girls are immediately recognizable as archetypes, which frees us to enjoy the Tilt-a-Whirl of their bad behavior. "Mean Girls" is at its heart a moral movie, even though, for the most part, it keeps a lid on the uppity moralizing. Waters and Fey trust us to grasp the movie's subtexts on our own; they realize that the best way to get the movie's meaning across is to concentrate on keeping the action fleet and funny.

It doesn't hurt that all the actors seem to be having a great time. Lohan pulls off the tricky job of playing the straightforward nice girl without ever seeming stiff or bland. Fey appears as a likably no-nonsense math teacher -- it's a good example of how a performer can shape a small comic role into a character rather than a mere caricature. She's joined by some of her "Saturday Night Live" colleagues, including a few who haven't gotten the exposure they deserve: In addition to Gasteyer, Amy Poehler shows off her trademark comic dementia as Regina's silicone-inflated, valium-addled mom. And Tim Meadows plays a dry-as-dust school principal who's funny precisely because you can't imagine anything ever shocking him.

But the most marvelous performer of all may be Seyfried, as the loopy, innocent Karen. Seyfried (in her movie debut) carries on the proud and unfairly maligned comic tradition of the dumb blond. She acknowledges to Cady that, yes, she may not be all that bright, but she does have her special gifts: She taps her forehead, opens her blinking-doll's eyes wide, and asserts in her wispy voice, "I have a fifth sense!" In case she hasn't made her point, she elaborates: "It's like I have ESPN or something." Seyfried makes playing dumb seem easy, even though it requires an especially meticulous sense of timing: The space between lines is wavier, and it's measured not in beats, or even half-beats, but eighths and sixteenths. Hit the wrong one, and you can make a joke thuddingly obvious. Seyfried gets every note right, riding the dippy waves of her role like an expert surfer.

"Mean Girls" isn't a particularly deep picture, but it does have some weight and ballast: Unlike many contemporary comedies, it doesn't just glide by like a forgettable, overdecorated parade float. It has an appealing prickliness, a quality that intensifies, subtly, both its good humor and its innate sense of right and wrong.

"Mean Girls" may do well with teenagers, but I think grown-ups are its truest audience. Getting through high school is rough for most of us. By the time we've made it through the battle zone, we deserve a lifetime's worth of good movies on the subject. We've earned the right to look back on it all and laugh -- even if that laughter comes with a sting.

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