CANNES (Reuters) - Obsession with celebrity is the focus of Italian director Matteo Garrone's new movie "Reality" at the Cannes film festival, one of two pictures in the lineup exploring the corrosive power of instant fame and the desire to be watched.

Garrone is best known for his last film, the gritty "Gomorrah" about a Naples crime syndicate. But with "Reality" he switches gears, creating a modern day fairy tale whose protagonist's soul is slowly and inexorably eroded by the lure of fame.

The second film, screening outside the main competition on Saturday, is "Antiviral," the debut feature of Brandon Cronenberg, son of Canadian director David Cronenberg. Its plot follows a clinic worker who sells fans injections of viruses harvested from sick celebrities.

In "Reality," Lorenzo is an affable Naples fishmonger and loving father and husband whose family convinces him to try out for the reality TV show "Big Brother."

Garrone chose as his main actor Aniello Arena, whom he discovered working in a prison theatre troupe. Arena, who is still serving his term, was allowed out of prison during the days to film but returned to custody in the evenings. He was not allowed to accompany the rest of the cast to Cannes.

"Never give up your dreams!" Lorenzo is told by the television crew who audition him for a spot on the show. Lorenzo is convinced it's only a matter of time before he receives the call saying he's been picked, and his status in his small community gets an instant lift.

As the days drag on and the call doesn't come, however, Lorenzo's obsession grows, and his hold on reality wavers. He starts to believe that crew from the TV show are spying on him, to determine if he would be a good pick for the show.

"What are they thinking about me?" he worries in his mind, in which he already plays a starring role. He sells his fish business so he'll have money to fix up their home.

"So it will look good in interviews," he explains to his wife, played by Loredana Simioli.

The audience is kept in suspense for much of the film, wondering whether the call will come that will release Lorenzo from his self-imposed torture and normalize his family relations, which have deteriorated.

Garrone is a fan of long pans in his latest film, which capture the beauty of a crumbling Naples while at the same time adding to the sense of voyeurism.

The movie opens with a sweep of the southern port city seen from above, gradually focusing in on a golden carriage drawn by two white horses and a footman in red breeches. When a bride and groom emerge, we see them enter their version of a fairy tale wedding - presided over by the host of Big Brother.

Garrone said it wasn't his goal to judge society's obsession with celebrity.

"What we were trying to do was to portray with great love a character while denouncing an aspect of society, but the aim was not at all to be critical," Garrone told a press conference.

"We didn't want to provide any answers," he added.

As for Cronenberg, celebrity obsession is part of something bigger in human society.

"I think that world is fascinating, both because of how grotesque it can be and how much it's really just one version of a much broader human impulse to deify and eviscerate," the young director told Screendaily.com.

Tags: Reality TV