Hunky Christian Bale lost more than four stone to achieve a 'walking scarecrow' look for The Machinist, director Brad Anderson tells Michael Dwyer

A CREEPY and tantalisingly revealed psychological thriller, The Machinist features a hypnotic central performance from Christian Bale as a factory worker haunted by his past and suffering from such a severe form of insomnia that he hasn't slept in a year.

In a film heavy on brooding atmosphere and unsettling developments, nothing is more startling than Bale's skeletal physique. The actor lost 63 pounds, shedding all the muscle he built up for American Psycho and Reign of Fire, and, in the many scenes where he is seen shirtless, his bones protrude through his pallid skin. Not since Robert De Niro piled on the fat to play the older Jake La Motta in Raging Bull has an actor demonstrated such extreme dedication to his craft and taken such risks with his health.

"On the day before Christian had a scene with his shirt off, he wouldn't drink any liquids for 24 hours, so he dehydrated his body to look even more sinewy," the movie's director, Brad Anderson, explained when we talked in London recently. "We didn't really have any discussions about the weight issue for The Machinist, but in the script the character is described as a walking scarecrow, so it was pretty implicit that he was going to have to lose some weight.

"I didn't realise that Christian would go to the lengths that he went. It wasn't a condition of playing the part, but it was necessary, I think. You needed to know that this character was that tormented, was literally being consumed by his own guilt, so it was important for him to look gaunt."

Asked about the diet on which Bale subsisted during the production, Anderson says Bale had no specific diet.

"He basically just stopped eating. We would see him occasionally gnawing on an apple, but the diet really was no diet. I guess that was the only way he could do it. He's one of those actors who really immerse themselves in their roles - the character, the accent, the look. Losing all that weight, he really became an insomniac like the character he plays in the film."

When I raise the question of Anderson's responsibility to, and for, his leading actor, he replies: "I was freaked out by Christian's condition, but kind of weirdly thrilled because I knew he would look pretty phenomenal on screen. If he was going to starve himself like that, it was my job to really exploit it, so to speak, cinematically to make it work within the context of the story.

"In the script, for instance, there were no scenes where he's walking around half-naked in his apartment, but then if we didn't have those scenes we wouldn't have got the full effect. Christian knew his limits as to how far he could push himself. Thankfully, his wife was with him for the shoot and monitored his condition. Of course, being in Barcelona, it was hell for him because the rest of us were having these amazing meals."

I note that Bale has built himself up again to play the title role in the imminent Batman Begins. "Christian's weight fluctuates all the time," Anderson says. "He told me he plans to do this Werner Herzog movie, a dramatic version of Herzog's documentary Little Dieter Needs to Fly. Christian is going to play a prisoner-of-war in southeast Asia, so he's going to have to lose another 15 pounds. The guy's committed."

The Machinist is Anderson's fifth feature film as a director, but none of the others was released here. I mention that I had attended a festival screening of his second film, Next Stop Wonderland, a charming romantic comedy of a couple whose paths almost converge many times before they finally meet and fall in love with each other in the final reel. Nothing about that film would prepare the viewer for the intense experience that is The Machinist.

"Yes, it is a little different," laughs Anderson. "My first movies were romantic comedies, so this is a detour. But before I made The Machinist, I did a movie called Session 9, which was much more bleak. It's a straightforward horror movie, really, so that was my first foray into my darker side."

Scott Kosar, who scripted The Machinist, was in a graduate screenwriting programme at UCLA when he happened to pass a machine shop and began to wonder, as one does, if machinists have existential crises. Anderson says that Kosar was heavily influenced by Dostoyevksy when writing the film, in which the Bale character's bedside reading is The Idiot.

"The big challenge of making puzzle movies such as this," Anderson says, "is for the audience to have the same moment of epiphany as the character, and at the same time. You don't want the audience to get ahead of the character, so you're doling out the clues in a way that lures in the audience without laying it all out too soon - or, on the other hand, being so oblique that the audience doesn't care."

Several US companies liked Kosar's screenplay, but were reluctant to make the film because it was so dark.

"At one point, Working Title were going to make it with the Coen brothers producing it, which would have been cool, but they opted out after a while and it landed in my lap. Then Christian happened to read it and he called me. His enthusiasm was so clear right away that I knew there was no point in looking for anyone else to play the lead, but it still took two years to raise the money."

When Anderson failed to secure US finance, he turned to Spain, where Session 9 had been quite successful, and he secured backing from the Spanish company Filmax.

"They weren't put off by the darker nature of the story,whereas most American producers wanted me to lighten it up, which would have been ridiculous," he says. "European producers are more open to stories that have a certain ambiguity and are challenging. In the US, even smaller non-studio production companies try to emulate the studio system. I think that's to their disadvantage because they end up making some really bad small movies with lots of compromises."

Has Miramax led the way in that respect? "I think so. I had my run-ins with Miramax over Next Stop Wonderland. We sold the movie to them at Sundance, which was thrilling at the time because it was just my second movie and Harvey [ Weinstein] was saying how much he loved the film. Of course, two months later they wanted me to cut the hell out of it and change the ending. It was just a nightmare, and one a lot of filmmakers have gone through.

"If you take a stance against Harvey and say you really appreciate his ideas but that you don't want to change your movie, they can simply say they don't want to release it and you're in a bind. Your movie sits on a shelf, or they release a compromised version based on Harvey's ideas."

Even though The Machinist is set in an anonymous US city, Anderson describes shooting it in Barcelona as "a blessing in a way" because he had full creative control. "The world in which this character lives is indefinable in a way," he says. "There are no culturally specific details. I like that aspect of the story because it alienates him that much more and that makes the movie spookier.

"Had we shot it in LA, we would have had a Starbucks or a McDonald's in every shot, and that would have been much more specific. We also had an entirely Spanish crew, who were great, even though I don't speak any Spanish, but most of them had enough English for us to get by."

Nevertheless, it was a difficult shoot. One sequence involved sending Bale and some of the crew into the Barcelona sewers. "We banged that out in one day," Anderson says. "We just wanted to get it over with. We offered Christian rubber boots to wear under his clothes, but he refused."

Early on in the shoot, Anderson sprained his ankle and later put his back out. "I directed one half of the movie on crutches and the other half lying flat out on a gurney," he says. "It was definitely a trial for me, but every time I started to whimper, I looked over at Christian and I knew I wasn't suffering nearly as much as he was."

The Machinist opens next Friday