'13 Going on 30': Cheerful fantasy floats on magic dust

Fashion-magazine editors may well wish to picket the new Jennifer Garner comedy "13 Going on 30," which breezily suggests that their jobs easily could be performed by any random 13-year-old. As editorship, depicted here, seems to consist of equal parts scheming, squealing and attending fancy parties, perhaps director Gary Winick and screenwriters Josh Goldsmith and Cathy Yuspa are on to something.

But grown-ups really aren't the target audience for this film, a cheerful fantasy about an unhappy seventh-grader named Jenna who is transformed, with the help of some magic dust, into her 30-year-old self. It's essentially "Big" with breasts, but with a time-travel twist. Tom Hanks' character magically grew up, but still remained in his childhood world; Jenna has been zapped into her future, with her childhood friends grown up (including Matt, the chubby boy next door, who's turned into Mark Ruffalo) and her parents aging.

Movie review Showtimes and trailer **½ "13 Going on 30," with Jennifer Garner, Mark Ruffalo, Judy Greer, Andy Serkis, Kathy Baker. Directed by Gary Winick, from a screenplay by Josh Goldsmith and Cathy Yuspa. 100 minutes. Rated PG-13 for some sexual content and brief drug references. Several theaters.

The newly grown-up Jenna is thrilled to find that she has a dream job at Poise magazine, a smartly retro New York apartment, and a vast wardrobe of cute pink outfits. She's less charmed, though, by the dawning realization — with the help of a reluctant Matt — that her grown-up self really isn't very nice, and sets out to turn herself into a better person.

Ho-hum, seen it before — but "13 Going on 30" has a couple of secret weapons, namely the snappy pace set by Winick (whose "Tadpole" was a funny, ultra-low-budget tale of a very different kind of teen fantasy) and the star power of Garner, who has the gawky sweetness here of a small-town prom queen. A gifted physical comedian, she proudly totters about in her stiletto heels — she spends most of the movie seemingly on the verge of falling over — blinking her big eyes at this strange new world. Though initially mystified by new innovations such as cellphones and thongs, she quickly adapts. "Can you tell I'm wearing underwear? 'Cause I totally am," she tells a friend after dressing up for a party, with perfect teen intonation.

It's actually a small problem with the film that you don't quite buy Garner as a 30-year-old — she's so in touch with her inner 13-year-old here, and so young-looking with her athletic figure, perfect skin and innocent smile, she looks barely in her 20s. (Garner is actually 32, which must be a triumph of either good genes or moisturizer.)

But with Ruffalo, whose chocolate-voiced vagueness makes him an enigmatic dreamboat here, she finds a genuine chemistry. You find yourself rooting for the two of them, despite the predictability of the premise. Turns out "13 Going on 30" has just a bit of magic dust of its own.

Moira Macdonald: mmacdonald@seattletimes.com