The 24-year-old, who became a household name in "High School Musical", was in Venice on Friday for the world premiere of "At Any Price", set in the cut-throat world of agriculture in which he plays Dean and Dennis Quaid his father Henry.

Efron's appearance on the Lido island across the water from the Canal City drew crowds of screaming girls begging for his autograph, and came a few months after he walked the red carpet in Cannes with another small-budget drama "The Paperboy".

Directed by Ramin Bahrani, At Any Price blends family drama with a searing attack on big business and chasing profits whatever the cost, as farmers in Iowa cut corners and cook the books in order to fulfil the mantra "Expand or Die".

"All I have, really, is the ability to look back at my elders and the people that I really respect in this industry, the actors that have been here before and really made an impact ... and I put myself in their shoes," Efron said.

"I sort of stand here with, say, two roads in front of me," he told reporters after a press screening of the film and ahead of its red carpet premiere at a glitzy evening gala.

"One (is) the easy path ... towards money and the other one being towards playing more interesting roles that I don't have all the answers to, or going with Ramin into the cornfields for a couple of weeks.

"It seems like the choice that I respect more. I'm following my gut here and this is what I want to be doing, you know. I'm hungry for it."

Efron is one of several rising Hollywood stars in Venice this year, along with Selena Gomez ("Spring Breakers") and Shia LaBeouf ("The Company You Keep").

Venice organizers are hoping that young blood will help compensate for the lack of A-listers appearing at the world's oldest film festival this year.

For director Bahrani, At Any Price contains important themes of corporate greed and economic desperation that are being felt the world over.

"I don't want to say what the moral of the film is. I don't know," he said.

"I wanted to ask questions, like what happens when you value expansion more than your community, more than yourself? ... Where have we gone in a world (where) the people who profited the most have gotten away with it and are dancing on top of everybody else?"

He likened Efron to more established actors like Johnny Depp, Tom Cruise and Paul Newman.

While some critics may argue such comparisons are premature, early reviews of the film have singled out Quaid and Efron for their performances.

"Continuing to distance himself from his origins as a pretty-boy teen idol, he (Efron) brings an intense, brooding stillness to the screen here, simmering with the frustrations of small-town entrapment," wrote the Hollywood Reporter's David Rooney.

(Editing by Steve Addison)

• A Permanent Economic Emergency