Your character undergoes physical and emotional transformation over the course of the film. Did you approach the two modes of Erik Heller differently?
Bana: The film was shot-- it was chronological, in the sense that we did start in Finland where I had the beard, and all the hair and the fur, and then we went to Bavaria, and we were actually in the cabin, so it actually did kind of work that way so by the time I'd shaved the beard off we were in Berlin and shooting that stuff. So mentally that helped and you were able to kind of split the movie in two halves. Productions don't usually take that into account. You're usually just jumping around back and forth, but in this case, the production logistically helped us. So, yeah, it was kind of like two different characters. I also liked the fact while it's kind of a loss of innocence for Hanna, it's kind of a loss of innocence for Erik, as well, he's going through it a second time as a human being. You know, there is a redemptive storyline for Erik -- I mean, he's responsible for Hanna -- and I really enjoyed that aspect of his journey.

Were you intimidated at all by the elaborate, uncut fight scenes you had to do?
Bana: It's scary on the one hand when the director tells you that the fight you've been learning is gonna be all one shot, but to a large degree it's kind of the antithesis to how those movies are usually made, so I was absolutely so excited to get the chance to do it, and its that rare moment in movie-making where the crew really does become, it becomes sport, and you're a football team, and everyone has to be bang-on for each take. We shot that in magic hour, although we rehearsed it all day, and then only had a window of about an hour, 45 minutes to nail it, and I think we did six or seven takes, with no real time to review each take at the end. So really exciting.

How much rehearsing did you do?
Bana: Generally, not a whole lot. We rehearsed in general, and we had a lot of fight scenes, so we got to a point where we were able to learn choreographed stuff really, really quickly. So in actual effect, it's more important that you get proficient at the fighting, and then learn the choreography close to doing it, so that it's fresh. You're so set in your rhythms that we tweak it on the day, as well. We did change it. We did have a day, actually, when we realized the camera can't get there, so it's gotta come in later, and that and that. You also have to have the ability to go with the changes in the environment, as well.

When you're choreographing fight scenes, accidents happen. Was there any concern when you were sparring with Saoirse?
Bana: You do get paranoid about it. Not about getting hurt. The only thing I get really paranoid about on a movie set where things are very physical is you cannot get sick and you cannot get an injury. Because I don't care what some people say, you actually can't do these fight scenes. Like if you hurt yourself properly, you can't do them. You can't do those things properly. So you have to go for it, but you're really hoping you're not going to tweak an ankle or, for me, like a back issue, something like that. You have to remain in shape through the whole production. It's not just about showing up on a day one and being ready to go. You have to then hopefully maintain without getting yourself or your co-star in trouble. So that's the thing you're kind of worry about in the back of your mind but yeah, you are coming into contact but, bruising isn't an issue, it's more about you tweaking an injury, especially for Saoirse. I wanted to be careful. The physicality has to be convincing, but at the same time you have to be careful.

You've obviously done a little traveling in your day. Were any of these places new to you?
Bana: Finland. I'd never been to Finland before, and that was pretty amazing. Berlin was and wasn't --I've been there many times on film sets or junkets, but that never counts when it comes to seeing a place. It was very cool to be there for a couple of months and to experience East Berlin properly, and get into the city. That was my favorite part of the whole shoot, actually, being there for an extended period of time. I didn't go to Morocco, in the end, because my character doesn't go there. But I've done Morocco in the past, so at least I got to hear the stories. But yeah, it's a cool part of the job. I remember a couple of our locations in Finland where you'd get to base camp, then you'd take a four wheel drive ten or fifteen minutes to a pre-arranged spot, then they would put Saoirse and I in the back of an enclosed toboggan behind a Ski-doo, and it would be another ten or fifteen minutes Ski-doo ride through the forest to get to a location. That's the sort of thing you don't forget in a hurry. That was pretty cool.

What do you think of the nerve-rattling Chemical Brothers soundtrack on the film?
Bana: [Director] Joe [Wright] obviously has a close relationship with them, and knew how he wanted to use them, so for me that's actually a character in the film, more so than a score usually would, when a collaboration is that tight and well-thought-out. I remember hearing Ridley Scott say once that when he hears directors say they aren't yet sure what kind of music they're gonna use for their movie, then they don't really know what movie they're making. It's a really interesting observation, and this is an example of a that in a really pure sense where the director is so clear about how important a role the music is gonna play in the final wash-up.

It sounds like you had a lot of fun on set. What was the least amount of fun you had?
Bana: It was all fun. Saoirse is such a sweet, fun young girl. She's not some precocious 30-year-old wrapped in a 16-year-old body. She's just a great young girl and our dynamic is actually more brother/sister than father/daughter so the only thing that we have to be careful about is not mucking around too much. We had a great crew, and you know Joe is wonderful with actors. I mean, the cold thing was something I'm completely not used to, being from Australia, but we were well looked-after. The funniest thing about that is we got issued a memo on how to diagnose hypothermia -- not in yourself, but in co-workers, because apparently its easier to diagnose hypothermia in someone else rather than yourself. You're not actually aware it's happening. And one of the things was "erratic behavior." And I thought, "Shit, we're on a movie set -- everyone's got hypothermia!"

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