Viggo Mortensen in Eastern Promises Peter Mountain/Courtesy of Focus Features

Some of the fight choreography is based on real Russian special forces techniques, apparently…
Yes, it's all part of their character. Where did they learn to fight, these three guys? Were they in the army, did they learn it on the streets, were they in some special forces, were they police? And that's part of their character is how they fight. So this was all a discussion.

Was it difficult convincing Viggo Mortensen to play the sauna knife-fight scene naked?
At a certain point, when we were starting, I said, "I want the action to start in this room and then open out and go over this barrier, and then there should be some other people in the steam bath who get in the way of the fight..." At that point, Viggo said, "It's obvious I'm going to have to play this naked." And I said, "Yeah, great." And that was really that discussion. He knew that, in terms of the level of reality in the movie that we were establishing, that if he had to wear this towel it would be silly, and if I were restricted in terms of what coverage I could do of the scene, it would be a big restriction in terms of what we could do and how I could edit it. So that didn't take very long.

You've said you shot the violence in Eastern Promises to be like the anti-Bourne: no quick cutting, you see, hear, and feel every blow…
For me, this is realism. My understanding of violence is that it's all body, it's all physical. When we talk about violence, we're not talking really about a building blowing up, we're talking about bodies being destroyed. And I take that very seriously because, you know, I'm an atheist, and I think your body is you. That's the first fact of human existence, and, really, the only fact. So if you kill somebody, to me that's an absolute act of destruction. There's no heaven to go to afterwards.

Do you think there is hypocrisy in the American ratings system when Ang Lee's Lust, Caution gets an NC-17 for sexual content whereas even extreme violence lands you an R?
Well, Lust, Caution has hardcore sex in it, and that's going to get you an NC-17. I don't think that's the issue in this case. It's not that cut and dry. They didn't see anything censorable in our movie. We knew we'd get an R.

What's your reaction when people tell you your violence is too graphic?
Well, as I said, I take this seriously. I think if you do it fast, and it's all aesthetic, and suddenly they're all lying there, you're letting your audience off the hook. They're not really having to experience this destruction of the human body that I'm talking about, and so it lets you off the hook in terms of violence; it turns it into an aesthetic event rather than into what, I think, is a purely physical event. I'm not saying that that's bad in terms of moviemaking. If you're making a big entertainment movie only, and you don't want your audience to get too nervous or too involved… I mean, those car chases in Bourne are actually physically impossible. Everybody knows that that's not for real, so I'd say that there's a larger fantasy quotient in a Bourne movie than in this movie. That's the difference.

Viggo seems like a pretty sensitive and poetic guy, and yet you've cast him twice as very violent men.
He's actually a hideous monster. Let me just put it this way: Don't cross him, okay?

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