Check out the brain on Barbie! Sure, she’s just a doll, but that doesn’t mean she has to be an airhead. Therein lies “Lady Bird” director Greta Gerwig’s inspired, 21st-century solution to bringing one of America’s most iconic playthings to life on the big screen. Combine that with the casting of Margot Robbie in the title role, and “Barbie” is already starting out on the right, perfectly arched foot. So what if this high-concept comedy falls a bit flat in the final stretch?

Barbie’s strength as a brand comes from her aspirational appeal. While some have rightly criticized the doll for setting unrealistic beauty standards, Barbie also showed girls they can do and be anything, as different models have portrayed her as president, a rocket scientist, even trans. You know who else sets unrealistic beauty standards? Movie stars. Like Barbie, they serve as role models, which is what makes Gerwig’s take on the ultra-popular toy line so darn smart. Robbie might be a dead-ringer for Barbie, but her moxie powers the performance. Gerwig has made the kind of family film she surely wishes had been available to her when she was a girl, sneaking a message (several of them, really) inside Barbie’s hollow hourglass figure.

That’s an admirable achievement, given understandably protective corporate parent Mattel — though let’s be honest, in the year 2023, it would be a shock (and box office suicide) if “Barbie” arrived without some kind of female-empowerment message baked in. This one checks all the right boxes, while making Ryan Gosling’s dumb-dumb Ken the butt of most of its gender-equity jokes. Boasting fresh tracks from Billie Eilish and Lizzo, the result is a very funny kids’ movie with a freshman liberal arts student’s vocabulary that tosses around terms like “patriarchy” and “appropriation” — pretty much everything but “problematic,” which the movie implies without actually calling Barbie’s legacy.

That’s the front on which Gerwig and Noah Baumbach’s script feels most daring. “Barbie” doesn’t just poke fun at Mattel; it comes right out and accuses the bestselling doll of setting back the women’s movement. As one indignant tween tells Barbie: “You’ve been making women feel bad about themselves since you were invented.” This reproach stuns Robbie’s upbeat character, who wakes up every day in the always sunny, hot pink fantasy world where Barbies come in all colors and body types. They win Nobel Prizes and occupy all 12 seats on the Supreme Court. And they’re occasionally pestered by dozens of Ken dolls, who are clearly insecure about being sold (and kept) separately.

Barbie Land, as it’s called, is an inherently hilarious alternate reality modeled on the dream that Mattel has been selling American girls since the doll was introduced in 1959. It looks a lot like the one they’ve seen in countless commercials, where flamingo-bright Barbie Dreamhouses inspire envy as a diverse collection of perky, positive-minded dolls smile and wave at one another (represented here by such avatars as Alexandra Shipp and Dua Lipa, Issa Rae and Ritu Aryu, Hari Nef and Sharon Rooney). It’s a wild pop-art space, all but exploding with supersaturated color, where the doll heads appear lower contrast and backlit, obliging us to squint to make out the actors’ faces.

You half-expect to see a giant hand reach in from the sky to interact with these lifelike toys, but that’s not how it works. Instead, Gerwig enlists Helen Mirren as narrator to lay out the rules, pausing now and then to spotlight specific costumes, interject vintage TV spots or cast shade on discontinued products — such as Growing Up Skipper, with her inflatable bust; pregnant Midge; or questionable-taste offerings like Sugar Daddy and Tanner, a flocked dog that poops plastic pellets.

Although Robbie’s blond-haired, fair-skinned Stereotypical Barbie seems to possess some abstract notion of herself as a toy, there’s a major disconnect between inventor Ruth Handler’s best intentions and the state of things in the Real World (where the movie spends roughly half its time): “Thanks to Barbie, all problems of feminism and equal rights have been solved,” Mirren sarcastically summarizes. One evening, in the middle of a dance party, Stereotypical Barbie blurts out, “You guys ever think about dying?” The next morning, she’s horrified to find her feet have flattened and a patch of cellulite has appeared. What could be threatening her near-perfect physique?

The answer lies in the Real World, where Barbie and Ken (Gosling’s Ken, not the ones played by Simu Liu, Kingsley Ben-Adir, John Cena and others) steer her pink Corvette, emerging at Venice Beach wearing matching fluorescent Hot Skatin’ ensembles. Yes, “Barbie” is one of those movies, like “The Smurfs” and “The Super Mario Bros. Movie,” where imaginary characters cross over to modern-day America — just infinitely more clever. Instead of using the premise as a setup for slapstick, Gerwig shows Barbie defending herself when some random guy slaps her butt, getting a knuckle sandwich in return.

The script is no less on-the-nose about its politics, and in any case, Gerwig and Baumbach’s social critiques seem more than reasonable. Their script merely emphasizes how lopsided the Real World remains in its treatment of women, up to and including Mattel’s corporate headquarters, where a working mom named Gloria (America Ferrara) holds an entry-level job, while the boardroom is packed entirely with guys in suits. At the head of the table sits Will Ferrell in what is easily the film’s laziest casting choice. (Hasn’t he played a dozen versions of this character before, most obviously starring as Lord Business in “The Lego Movie”?) Defaulting to Ferrell means passing up the chance to create a memorable original embodiment of the kind of men who run corporate America.

At the same time Barbie is experiencing her rude awakening, Ken’s busy filling his empty head with all the possibilities that “patriarchy” entails. In Barbie Land, Ken’s job is a deliberately ill-defined afterthought (basically, just “beach”), whereas in the Real World, dudes rule — an idea he takes back to Barbie Land with pointedly absurd results, brainwashing all the women into behaving like obedient housewives. The film’s draggier second half gets both silly and unabashedly strident, as Stereotypical Barbie seeks help from Weird Barbie (Kate McKinnon), a damaged-goods doll with singed hair and messed-up makeup who serves as this girly-girl world’s Morpheus-like sage.

It’s upsetting (in a useful way) to see Barbie confronted with the overnight impact of rampant patriarchy, a concept that has rarely looked more off-putting than the frat-boy fantasy caricatured here. Think of it as the misogynist alternative marketed by old-school beer commercials, the polar opposite of Mattel’s mid-’80s “We girls can do anything. Right, Barbie?” campaign. While the Barbies plot to take back the government, Gerwig gives all the Ken dolls an over-the-top musical number, “I’m Just Ken,” which is so amusingly self-involved it risks subverting the very point the movie’s trying to make. If “Barbie” is all about centering and celebrating women, why let Ken steal the show?

Gosling is a good sport to play the slightly predatory, sartorially helpless pretty boy, as the spray-tanned ex-Mouseketeer parodies his popular “hey girl” persona, flexing both his muscles and a range of facial expressions all but lacking from his recent work. If Robbie’s Barbie sets an impossibly high bar for young women, then Gosling’s Ken reps an equally formidable male model, with his chiseled abs and cheekbones.

That factor hasn’t escaped Gerwig, who sets out to disrupt such unattainable aesthetic standards, calling out ways the doll’s idealized design can harm self-esteem and encourage eating disorders. She crams most of that critique into a single motormouthed monologue, which drew cheers at the premiere and which, on closer inspection, contains not a single controversial idea. In the end, the trouble with “Barbie” isn’t that it goes too far, but that it stops short, building to a conceptual scene between Barbie and her Creator (Rhea Perlman) that inadvertently underscores one of the movie’s few failings: It’s an intellectual experience, not an emotional one, grounded largely in audience nostalgia.

The power of nostalgia ought not be underestimated with a property like this, as much of Gerwig’s approach skews toward grown women and gay audiences who’ve owned the dolls — and for whom she’s embedded deep-cut trivia and hidden references throughout. The movie was clearly made by people who understand how kids’ imaginations work when playing with Barbies, even if Gerwig uses the project as the delivery device for what sounds like an undergraduate gender studies lecture at times. Most of its points are positive ones for young girls to hear, while those that earned the film its PG-13 rating will fly right over their heads as they feast on all the eye candy, including re-creations of classic looks by Jacqueline Durran (costumes) and Sarah Greenwood (production design).

It’s kind of perfect that “Barbie” is opening opposite Christopher Nolan’s “Oppenheimer,” since Gerwig’s girl-power blockbuster offers a neon-pink form of inception all its own, planting positive examples of female potential for future generations. Meanwhile, by showing a sense of humor about the brand’s past stumbles, it gives us permission to challenge what Barbie represents — not at all what you’d expect from a feature-length toy commercial.