The movie, which had its premiere at the Venice film festival, is directed by Harmony Korine and stars Gomez and fellow Disney graduate Vanessa Hudgens as bikini-clad revellers on a drink and drug-fuelled orgy of beach parties and pranks.

The camera zooms in on scantily-clad teenagers gyrating to the music, local drug dealers snort cocaine from writhing, topless girls and mobsters cruise the streets of Florida in Lamborghinis in a hedonistic portrait of the "American Dream".

Gomez plays Faith, the least wild of a group of four young college students on their mid-term "spring break", and the actress admitted that some fans would find the movie shocking.

"Obviously I know that coming from Disney Channel gives you kind of a brand in a way," the 20-year-old said in Venice after the movie was screened to the press.

"People do put a label on you. I know that I have younger fans, and this is an opportunity for myself to kind of grow. It is a little shocking, I think, for the younger audiences ... but I think it was right for me.

"I did things I didn't even know I could do on the movie and I do think it was because I trusted Harmony."

Gomez, who rose to fame as a teenager on Disney show Wizards of Waverly Place and enjoyed success as a pop singer, added that she turned down the opportunity to play one of the more racy characters.

"I just didn't think I was ready for it, and I do think that Faith is right for me at this time in my career and in my life. Of course eventually I'm going to kind of work my way up to that I think," she added.

Reaction to the movie in Venice has been mixed. Korine is described as an "enfant terrible" of US filmmaking who is best known for writing controversial movie Kids and directing the experimental Julien Donkey-Boy.

Some critics found Spring Breakers implausible and pretentious, while others described it as "wild" and "compelling" and a breath of fresh air at a film festival dominated by more serious, sombre cinema.

Robbie Collin of Britain's Telegraph argued that Korine did not go far enough.

"Beneath its Terry Richardson-esque porn chic surface, Spring Breakers is no racier than a mainstream Hollywood teen comedy, and Korine doesn't seem to know what to do with his film's incredibly timely, potentially dangerous premise," he wrote in a three-star review.

In the film, the four friends join hundreds of others whose sole aim is to get drunk, stoned and naked.

Korine said he was aiming to capture the spirit of young people today who are often misunderstood.

"This idea that there is no soul ... with the new generation is not true, but it's just that the soul has morphed.

"It's about kids that are raised on video games, and raised on YouTube clips and raised as television babies, and so the step from watching to doing is sometimes very, very small."

In the story, things turn sour for Faith and her pals when police bust a party and throw them into jail. They are bailed out by local drug dealer and rapper Alien, played with exaggerated relish by the Oscar-nominated James Franco, who spots them in court wearing only bikinis and decides to take them under his wing.

Faith feels increasingly uneasy as Alien tries to seduce her, and leaves her friends before they are drawn into an increasingly dangerous cycle of sex, money and violence.

REUTERS