Von Trier's controversial new film, Nymphomaniac, charts the life of a sex addict from youth to middle age. The picture sparked outrage this week when its trailer was mistakenly shown to an audience of schoolchildren in Tampa, Florida. And yet, despite Nymphomaniac's explicit content, its co-star Stellan Skarsgård insisted it should not be considered a pornographic movie."Pornography has just one purpose, which is to arouse you. To make you wank, basically," Skarsgard told the Guardian after a screening of the film in Copenhagen. "But if you look at this film, it's actually a really bad porn movie, even if you fast forward. And after a while you find you don't even react to the explicit scenes. They become as natural as seeing someone eating a bowl of cereal."Nymphomaniac stars Charlotte Gainsbourg, Von Trier's regular muse, as the anguished Joe, who recounts her experiences to Skarsgård's lonely, bookish bachelor. Flashbacks lead the viewer from casual encounters aboard a commuter train to sadomasochistic sessions inside a sterile office, while the plot finds room for a supporting cast which includes Shia LaBeouf, Christian Slater, Willem Dafoe and Jamie Bell. At one stage, Uma Thurman crops up as a vengeful wife, escorting her infant sons on a grisly guided tour of Joe's apartment. "Would it be OK if the children saw the whoring bed?" she asks brightly.For good measure, the film also marks the screen debut of 22-year-old British actor Stacy Martin. The former model dominates the opening sections, playing the title character in her teens and 20s. But Martin explained that a body double was used for the more explicit scenes. "She was called Cindy and I think she's an actual porn star in Germany," Martin said. "I would do my thing and then she would do her thing. You're doing a scene and suddenly it switches and becomes a porn set. It was like two different films being made at the same time."Despite the precautions, co-star Gainsbourg admitted she had qualms over some aspects of her performance. "The sex scenes weren't so hard," she said. "For me it was all the masochistic scenes. Those were embarrassing and, yes, a little humiliating."Nymphomaniac was shown to the press at a private preview, where it clocked in at four hours long. During the intermission, between the horrors, the guests repaired to an upstairs room for coffee and biscuits.One notable absence at the screening was von Trier himself. The director has refused to speak to the press following his contentious remarks at the 2011 Cannes film festival, where his previous movie, the apocalyptic drama Melancholia, won the best actress award for its star Kirsten Dunst. Discussing his German parentage at a press conference in Cannes, von Trier labelled Israel "a pain in the arse" and joked that he was a Nazi and sympathised with Hitler "a little bit". His comments prompted a media frenzy and led the festival first to demand a public apology and then to banish him from the event."The explosions in Cannes had nothing to do with Lars," said Skarsgård, who has now worked with von Trier on six films. "Everyone knows he's not a Nazi, and it was disgraceful the way the press had these headlines saying he was. That shocked him and hurt him, and that's why he doesn't want to talk, because he feels insecure. He feels that whatever he says can be turned into something outrageous."Skarsgård blamed both the media, for misrepresenting the tone of the director's remarks, and the Cannes festival organisers, for overreacting to the controversy. "The cowards at the Cannes festival not only demanded that he apologise, which he did, but then banned him, probably under pressure from the sponsors," he said.Reviews of Nymphomaniac are embargoed ahead of its Christmas opening in Denmark, with the UK release set to follow in March, but guests emerged from the Copenhagen screening looking a trifle shell-shocked by the experience. Perhaps most surprising is news that the four-hour Nymphomaniac is billed as the "abridged and censored" version. Von Trier now plans to release his uncut five-and-a-half hour edition sometime in 2014. Reports suggest it may well premiere at next year's Cannes film festival. Organisers are advised to have the smelling salts on tap.• What do you think of the trailer for Nymphomaniac?• Nymphomaniac still hardcore, even as Lars von Trier gives up final cut• This article was amended on 5 December 2013 to remove an allegation that could not be verified.(theguardian.com)ANN.Az