Plenty has happened to Jamie Bell since he gained fame four years ago in Billy Elliot, but nothing more horrifyingly memorable than the time he was made to suckle a cow.
''The hairs get in your mouth, and it's hot,'' Bell says, frowning. ''It's really disgusting.'' The occasion still gives his antagonist, 29-year-old director David Gordon Green, the giggles. ''That was awesome!'' he says. ''My parents were in town and I wanted to show off. My dad bet me five bucks I wouldn't be able to get him to do it.'' Dad lost the bet, but the joke was on Bell. ''Every time I finished [a take], David would be laughing his ass off,'' he says. ''He did it as a quick dig at me a little let's-make-Jamie-a-fool.''
The Udder Affair transpired in a Georgia barn on the set of Undertow, Green's follow-up to 2003's All the Real Girls. A messy, tangled Deep South yarn, the movie follows two young brothers (Bell and Devon Alan) on the run from their murderous uncle (Josh Lucas). ''We were filming in some nasty locations,'' says Bell, who spent long hours trading his meaty North England twang for a Southern drawl. During a six-week shoot caked in mud and blood and rust, he endured infrequent baths, swarms of famished chiggers, and belligerent rednecks. In a cruel imitation of art, he also stepped on a nail. ''Everyone found it funny because it happens in the film,'' says Bell, now healed. ''It was also funny to see me, who is always so light on his feet and bouncing around, in a wheelchair.''
In fact, little in Undertow would make folks think this is the same fellow who pliéd around in 2000's Billy Elliot, the acclaimed drama about a working-class boy who dreams of becoming a ballet dancer. Just 14, Bell was thrust from a single-parent English home onto the world stage, ultimately beating out Russell Crowe and Tom Hanks for a best-actor BAFTA, Britain's Oscar. Two more movies 2002's Nicholas Nickelby and the straight-to-video war thriller Death-watch and some fashion modeling followed. ''Going through that . . . does mature you in a very quick way,'' says Bell, a lifelong dancer who still taps when he gets the chance. Now 18, he has finished high school and lives with friends in London, where he must wear a baseball cap to avoid notice. ''He's spent a lot of time around adults,'' says Billy Elliot director Stephen Daldry. ''But he's got an incredible playfulness, and he spends a lot of time being a genuine teenager.''
The endearing boy and the fresh grown-up both show up to a recent lunch. Taking a break from filming Peter Jackson's hush-hush King Kong remake in New Zealand (he's among the crew that nabs the beast), Bell sits in a Manhattan rooftop bar overlooking the Empire State Building, masterfully dodging queries about that big ape and his own romantic life. Wearing sneakers and a ratty Adidas T-shirt, the actor fields calls from chums on his cell, refuses to finish the burger his manager insisted he eat (''It tastes like s---,'' he whispers. ''I'll just get McDonald's later''), and laughs himself silly when his interviewer twice spills some coffee. ''That transition from a kid to a man is something that I've had to make over the past year and a half,'' he says. And he's not always proud of how the kid behaves. ''I always look back and say, 'God, Jamie, you are so bloody stupid sometimes,''' he confesses. ''It's a hard game to play . . . just to come across as an okay guy. I'm still learning.''