New Moon reveals the ancient secret of the Quileute tribe
By Tim Masters
Entertainment correspondent, BBC News
She's 18, he's 109. And there are topless scenes galore. It sounds like the most politically incorrect movie of all time.
But this is New Moon - the second movie in the Twilight vampire saga - and all those bare chests belong to buff young men with waxed pecs and six-packs.
There are more than 100 fan sites devoted to Twilight
"You get a lot of nipple shots in this movie," laughs Robert Pattinson, the actor who plays the 109-year-old vampire Edward Cullen.
Since the first film came out a year ago, Pattinson has become a heart-throb to teenage girls across the world, and also a favourite target of the paparazzi.
Based on Stephenie Meyer's best-selling novels, the first Twilight film set up Edward Cullen's love affair with mortal heroine Bella Swan, played by Kristen Stewart.
The New Moon sequel sees the romance become more intense until an incident at Bella's 18th birthday party makes Edward decide to leave her in an effort to protect her from supernatural danger.
Bella begins to heal her broken heart with the help of her childhood friend Jacob Black (Taylor Lautner), and discovers that he has some supernatural secrets of his own...
Obviously I spent a lot of hours in the gym
While most of the bare-chested action comes from members of Jacob's mysterious Quileute tribe, it's no surprise that Robert Pattinson loses his shirt once or twice.
"I was really terrified," says Pattinson. "I hadn't worked out at all, and I saw Taylor at the beginning of the year and I did feel incredibly inadequate."
With Lautner stepping into a central role in New Moon's love triangle, he set about beefing up his body in the gym.
Such is his transformation after Twilight, even Bella seems taken aback when she meets her friend: "Hello biceps," she quips.
She may as well have held up a flashing neon sign saying: "HUNK ALERT!"
"Obviously I spent a lot of hours in the gym," says Lautner, during the film's launch in London.
"The most important part for me was the eating process. I had to double or triple my calorie intake per day. It was a matter of eating every two hours, disgusting things like meat patties and raw almonds and sweet potatoes."
Twilight star Robert Pattinson says he is always surprised by his fans
The acres of bare flesh will delight Twilight's core female teen audience.
The statistics around the Twilight series speak for themselves: The books have sold 85m copies and have been translated into more than 20 languages.
Last year, the first film's American opening of $69m (£41m) beat the Bond movie, Quantum of Solace. And it took $383m (£229m) worldwide - just ahead of Oscar sensation Slumdog Millionaire.
The world of Twilight is populated by fans called "Twi-Hards", or by Pattinson fans who refer to themselves as "Robsessed".
Pattinson still seems genuinely bewildered by the amount of attention he generates.
Asked how he prepares himself to face thousands of screaming fans, he tells the BBC: "I always find myself wearing a lot of layers as well so they can't see you hyperventilating - that's a good preparation technique."
I think they don't really realise what has been going on in America
Robert Pattinson - on his family's reaction to his fame
Pattinson admits that his fame has meant he finds it difficult to lead a normal life in public, but he does manage some freedom.
"There's always places you can disappear to. It just involves a little bit more thought. You can't just wander around willy-nilly," he says.
"It's such a novelty to me still. If I'm still stuck in hotel rooms in 10 years and I haven't figured out any other way than hiding, it probably would annoy me a little bit."
And he misses not being able to drive in Los Angeles.
"I never had a car in London, and I only got my car in LA last summer, so I only really had three months driving without having 10 cars following me. I'm too scared to drive now, so that's a little annoying."
New Moon's director Chris Weitz - who previously helmed The Golden Compass - admits he cut himself off from the Twi-Hards while making the movie.
"I put myself on complete media blackout because I am the person who will be up at three in the morning having a heated discussion with a 14-year-old," he says.
Michael Sheen plays the leader of vampire clan the Volturi
"But since the movie wrapped, I've become a horrible Twitter addict, and the reaction to footage that has come out has been encouraging. It's been a source of inspiration during the post-production period."
And how are the stars' families dealing with their global fame?
"My family is embarrassingly proud of me," says Kristen Stewart. "My brothers get a little protective. I've made rules now that you can't go outside and scream at people with cameras."
Pattinson says: "My family live in London and I think they don't really realise what has been going on in America."
Weitz chips in: "They seem quite bemused in a lovely English way."
Whether this film will reach out beyond its largely female demographic will become evident when it goes on general release on 20 November.
But with ramped-up action scenes, giant wolves and a final act that shifts to sun-drenched Italy, Twilight is showing every sign of turning into a fully-fledged franchise.
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