Based on Alex Garland’s best-selling novel, and produced by the unsurpassingly hip “Trainspotting” team (director Danny Boyle, producer Andrew MacDonald, screenwriter John Hodge), “The Beach” follows a Gen-X backpacker named Richard (DiCaprio) on his search for a secret island paradise he’s only heard about. On the way, he falls for a woman named Francoise (Ledoyen), and she and her boyfriend join the quest. They finally reach the perfect beach after a series of cinematic adventures, including a jump off a 120-foot waterfall. They fish, they swim, they smoke a lot of pot. But before long, nirvana unravels; nightmarish violence ensues; “Road Rules” runs smack into “Lord of the Flies.”

Garland’s novel was hailed as a parable about rich, spoiled Westerners who defile the unspoiled Third World every chance they get, an ironic twist that haunted the eco-controversy surrounding the movie. In interviews, Leo has waxed on about the domination of Western culture, and how strongly he identified with Richard’s desire to escape a world soaked in American pop culture, movies and television. As king of that world, he should know.

Always uncomfortable with the Tiger Beat hysteria that accompanied “Titanic,” Leo took almost two years to settle on Boyle’s movie–the only one, he’s said, that wouldn’t bore him. (He flirted briefly with “American Psycho.”) “The Beach” harks back to Leo’s arty, uncommercial days, when his films (“This Boy’s Life,” “Basketball Diaries”) got good reviews and bad box office. Dark and visceral, “The Beach” is Leo’s postadolesent rebellion against his preadolescent fans–a titanic kiss-off to Leomaniacs.

All of last year’s PR headaches culminated in Leo’s parting of the ways with his publicity firm, Baker Winokur Ryder. The story was that BWR had promised Vanity Fair that Leo would be its February cover boy. But in October, Leo overruled his publicist and opted to do the February cover of Miramax-owned Talk magazine instead. (A BWR spokesman says that this incident was not the cause of the split.) “I do whatever the hell I want to do,” says Leo in the current Face magazine. “I’m not going to let anyone dictate how I should lead my life.” His next film, Martin Scorsese’s “Gangs of New York,” focuses on gang warfare in the 1800s. Celine Dion won’t be singing along to that one, either.