VANESSA HUDGENS recalls that when she first read the screenplay for her new film, “Bandslam,” her role was described as “deadpan,” “introverted,” “a bit off.”

“I said, ‘I’m so in.’ ”

For the enlightenment of those who have already celebrated their 11th birthdays, Ms. Hudgens has spent the last four years playing the sweetly smiling, sweetly singing Gabriella in the “High School Musical” movies, becoming the contemporary answer to Annette Funicello and helping make the Disney Channel the daily destination of tweens everywhere. Gabriella is the kind of gilded trap from which successful child actresses have struggled to free themselves since Shirley Temple, not always with graceful exits. Ms. Hudgens’s decision to counter her own image, therefore, seems as logical, and tactical, as any.

“Bandslam,” opening Friday, was directed by Todd Graff (“Camp”) and is set in a New Jersey high school whose culture is dominated by an annual battle of the bands. (“Think high school football in Texas,” one character explains.) There are heavy favorites, but that doesn’t stop the new student, Will (Gaelan Connell) from leading fellow outsiders toward rock ’n’ roll victory, especially after he’s asked to do so by an ex-cheerleader/killer vocalist/all-round hottie named Charlotte (Aly Michalka). Ms. Hudgens’s character, Sa5m (“The five is silent”), is an emo girl who speaks slowly because of a stutter, resembles Ally Sheedy in “The Breakfast Club” and is ostensibly the female lead, even if Ms. Hudgens argues to the contrary.

“I’d say Aly,” she said, when asked which actress has the starring role. “I’d say she’s the leading lady. I’m completely fine with the fact that I’m not the star of this movie. For me it doesn’t matter how big the part is, just as long as it’s a memorable character.”

It’s clear from the start, however, that Ms. Hudgens is the movie’s loaded gun and is going to go off spectacularly. At this, she giggled.

“It was great,” she said. “I feel like I only want to play characters that you get to see evolve, and you see Sa5m go on this journey. And I think it’s great for kids to see another person who’s so far off from the normal girl. It was awesome. My whole rock sequence at the end was — awesome.”

Casting Ms. Hudgens, despite her huge fan base, was something of a gamble. “Bandslam,” from an original script by Josh A. Cagan,” was reworked by Mr. Graff, who intended to tell “the story of Brian Epstein at 16.” What the results resemble more than anything is the Richard Linklater movie “School of Rock.”

“Thank you,” said the producer Elaine Goldsmith-Thomas, who bought the Cagan script five years ago. “I don’t take anything away from ‘High School Musical,’ but this is so not ‘High School Musical.’ ” But Ms. Goldsmith-Thomas’s concern points up the Hudgens “Bandslam” conundrum: How do you avail yourself of Ms. Hudgens’s following without positioning your movie as another tween musical? Especially when that movie is so music driven (and stars another Disney alum, Ms. Michalka)? The calculation is that as the actor ages (Ms. Hudgens is 20), so do her fans, and they’ll follow her into the older fare represented by “Bandslam” and Sa5m.

“I hope so,” she said. “I think once they see it, they’ll understand it is for an older audience. I just hope that people don’t think it’s the stereotypical high school musical.”

Ms. Hudgens has been doing the “High School Musical” movies since she was 16; before that, she appeared in “Thunderbirds, and had a role in Catherine Hardwicke’s dark, provocative “Thirteen.” But Gabriella was, and so far is, the calling card, and Disney the motor, behind Ms. Hudgens’s professional momentum.

“Disney is an incredible machine,” she said. “They really have it down and figured it out. There’s so much power with the channel. Kids will watch anything that’s on it. When these kids are put on these shows, the kids at home are living and breathing the channel, and they grow to love these people. It’s crazy.”

Ms. Hudgens’s relationship with Disney was strained two years ago when nude photos of her appeared online. A mention of it causes her visible pain: “It still hurts me to this day that someone would do that. But it’s the past, and I got over it, and I’m still working. So it hasn’t killed me.”

It certainly didn’t prevent her from appearing in another “High School Musical.” “I’m still in the third one,” she said with a smile. “You couldn’t do a third one without Gabriella.”

Given her experiences, it’s unsurprising that Ms. Hudgens “hates” the Web. She isn’t fond of paparazzi either. “We went to the restaurant next door yesterday,” she said at her Manhattan hotel, “and I look across the street and see lenses. They waited in their cars the rest of the day, so I stayed in my room the rest of the day.”

Does a lack of attention ever worry her?

“God, no, are you kidding?” she said. “It makes me a happier person. I say, ‘Thank you, Lord, for blessing me today.’ ”

In an industry where talented people can evaporate because of attitude, Ms. Hudgens seems precociously grounded.

“She was gigantically famous from the ‘High School Musicals,’ but I hadn’t seen ‘High School Musical’ at the time, because I’m not a 12-year-old girl,” said Mr. Graff, who added that Summit Entertainment and Walden Media, the studios for “Bandslam,” were eager that she be considered. “So I said, ‘I’m more than happy to have her come in and audition if she’s willing to do that.’ And she was cool about it.”

Ms. Hudgens isn’t resting on any laurels. Or resting at all. Having just finished “Beastly,” an update of “Beauty and the Beast,” she was heading off to Vancouver to shoot “Sucker Punch,” in which she plays a young woman confined to a mental institution, who fantasizes it’s a brothel.

“I’m always known as ‘that girl who’s singing in that movie,’ you know?” she said. In “Sucker Punch,” she added happily, “I get to fight and shoot a lot of people.”

this article was edited from http:/www,nytimes,com/2009/08/09/movies/09ande.html?hpw