It's spiritual, a man that has a past and regrets, but you can as a director take a shot, and there's something in the eyes and the face, you just can't fake it, you can't teach it, and I think Ed Harris has that quality.

I love a chance to shoot real locations, because in films in the earlier days before people traveled as much, it was exotic to see a film set in Switzerland, and that area has been taken over by CGI, mostly, and fantasy landscapes. It's unusual to see this much landscape, people say it's old fashioned. So what you're referring to is there was that period in the '50s and '60s when there were epics and you saw landscape.

I think Ed Harris is a conscious screen actor, so I think it was strong, it was like he put everything together somehow in 'The Way Back'. He likes, I don't want to say the method approach, because that's not really necessarily his way of working, but it was easy to do because of the location. He'd go off by himself, and they would make things.

Casting the right actor for the right part is some unspoken thing between the two of you to communicate.

Sixty-five days principle photography, five-day weeks, which is the only way I'll work. With my cinematographer Russell Boyd, we take as much time as possible before pre-production, looking at stills. The next most important thing: he will come to me and talk about lenses. And I'll see his plan, which is generally great, and I might talk about how the light will be, handheld or not? I talk very freely, and try not to talk specifically, just talk around it, because it can unlock all sorts of things.

So much of the work is intuitive. The resistance you detect is just that, a kind of evasion, a sense that too much analysis will inhibit creativity.

Movies tie things up in an arbitrary length of time, but I have always liked things that aren't fully realised.