The second film in a series about teenage vampires has become the fastest advance-selling movie of 2009 in the UK, taking £1m even before it has been released. Twilight: New Moon is the latest film adaptation from the four-part series of novels for teenagers by American author Stephanie Meyer. The films and books tell the story of a romance between a teenage girl, Bella, and Edward Cullen, a centenarian vampire, who is, however, eternally youthful. The novels have been international bestsellers with sales of around 85m copies worldwide. The latest film is sure to set girl fans' hearts a flutter as it is packed with good-looking actors playing vampires with waxed pecs and six-packs. The vampire hero of the films is played by 23-year-old, British actor Robert Pattinson, whose big break came playing Cedric Diggory in Harry Potter and the Goblet of Fire. Speaking to the BBC, Pattinson described his feelings of "incredible anxiety" about revealing his body among such a cast of well-muscled young stars. "I was really terrified," said Pattinson, "I hadn't worked out at all." Fans of the actor describe themselves as "Robsessed", a play on words between the actor’s name and the word obsessed. Meeting such fans at film premieres around the world can be a daunting experience for the young cast. Pattinson told the BBC how he prepares for such nerve-inducing, highly-charged events. "I always find myself wearing a lot of layers as well so they can't see you hyperventilating," he said.