'Crossroads': Britney's Fizzy Serving of Hot Pepsi

Oops, she did it.

It was only a matter of time before Britney Spears, the diabetic-shock-inducing pop tart whose audience seems composed chiefly of 10-year-old girls and 50-year-old men, would make her cinematic debut.

Following hard on the Jimmy Chooed heels of such songstresses turned, uhm, actresses as Janet Jackson, Mariah Carey and (Her Nibs) Madonna, Spears has crossed that line between Madison Square Garden and the multiplex marquee to stake her claim as a fully developed artist, one who needs, desperately, to explore yet one more of the many colors that are Britney in order to express herself more fully to the fans.

Oh, and make just a leeetle bit more money. Because, really, after all the platinum albums and Super Bowl commercials and HBO specials have come and gone, every girl knows that it's all about ancillary markets.

But let's cut to the chase. Is "Crossroads" worse than "Desperately Seeking Susan"? Yes. Is it better than "Glitter"? You bet your baby-blue rhinestone-encrusted thong. Can Britney act her way out of a Kate Spade bag? Not really, although she cannot be accused of overreaching. She hits her marks in "Crossroads," acquitting herself if not admirably, at least not shamefully. But let's be real: Streisand she ain't.

"Crossroads" finds Spears in a classic road movie, one in which issues are faced, demons slain, virginity lost and the day saved by – wait for it – a crucially timed karaoke contest. After graduating from high school, Lucy (Spears), who "worked really hard" to be valedictorian, decides to find the mother who abandoned her 15 years earlier.

She lights out for Arizona, joining her two estranged best friends (Zoe Saldana and Taryn Manning) and a mysterious hottie (Anson Mount) who is chauffeuring the other two girls to Los Angeles where one will compete in – wait for it – a talent competition sponsored by a record company. Will the three girls reconcile? Will the strait-laced Lucy undergo a startling makeover into a babelicious sexpot who gets the guy, nabs the record contract and sneaks in a heartfelt performance of Britney's new hit single, "I'm Not a Girl, Not Yet a Woman"?

Ya think?

It turns out that "Crossroads" is not a music video, not yet a movie, but more like an extended-play advertisement for the Product that is Britney. Withal it features competent direction from Tamra Davis, who coaxes life into what could have been a thoroughly moribund enterprise. Spears's co-stars all bring surprising dimension to unsurprisingly flat characters, and Davis and screenwriter Shonda Rhimes ("Introducing Dorothy Dandridge") use the car radio as a clever excuse for their star to burst out in her signature helium-propelled whimper.

Although teen sexuality is the driving force, theme and raison d'etre for the movie, the filmmakers can be commended for portraying some of the real-life consequences of early sex and other reckless behavior – consequences that include pregnancy, date rape and all-around yuckiness. (Less realistic is the sight of a bunch of girls from Georgia – where the faucets run hot, cold and Coca-Cola – swigging nothing but Pepsi. But the corporate beast, even Britney's, must be fed.)

Still, it's that very sexual candor that makes "Crossroads" so problematic, straddling as it does the fine line that Spears has made a career of crossing, as she tiptoes ever so coyly between Mouseketeer and jailbait. Britney Spears's live show is missing only the two-drink minimum to qualify as a gentlemen's smoker, but throughout her performances the singer seeks to defuse the aggressive sexuality of her persona with occasional wrinkle-nosed, gee-whiz grins. She wants to have it both ways in "Crossroads," too, eagerly stripping down to her skivvies (usually pink) and exposing her navel (always pink), then swaddling herself in fuzzy sweaters (mostly pink) that here seem to have mysterious re-virginizing powers.

Whether the act is naive or cynical is up to Britney's audience to decide. But when that audience is composed of the aforementioned 10-year-olds, the fine line she's playing with becomes more problematic. What are tweens to make of a bubble gum idol who is giggling with her girlfriends one minute and swinging lasciviously from a pole the next? It's not for nothing that "Crossroads" has been rated PG-13, meaning that parents are "strongly cautioned." Put more simply, be afraid. Be very afraid.

CROSSROADS (PG-13, 94 minutes) – contains sexual content and brief teen drinking. At area theaters.