I think it's doubly important, now that we see so many people failing. When the norm is an anti-hero, there's a serious loss when you cannot portray a decent person on screen without it becoming slightly sentimental or feeling like it's unrealistic.

I'm aware now over the last 5 or 10 years that when you do an accent, you really have to kind of get down to the nitty gritty and go into the phonetics of it, if necessary. Find out not just the sounds but the rhythms and the music - or lack thereof - in a particular accent.

I don't plan in terms of career ambitions. The only career ambition I have is to work with people who are going to bring you up and elevate your performance. They'll let you know things that you didn't know already and bring you places that you might not have gotten to otherwise.

It's interesting going between small parts and then bigger roles where you carry the film. If the writing is good, and if the people involved have integrity, then you'll do it, even if it's only five minutes on screen.

So, to get to play somebody who was insisting on it, in spite of all the evidence was very liberating and exciting. It went quite deep. I suppose I reference a kindness and humility that I would have seen in my parents' generation, a little bit more than now.

My grandfather played a mandolin, so I got my hands on that. Then on down to a banjo, and I found I couldn't play any kind of soft or mournful music with that so I took up the fiddle in my late 20s or early 30s - and that was far too late. But it keeps me off the streets. It has been a love of mine since I was 17 maybe.

I started hitching about the country when I was 16 or 17 years old. I found the music that was played around the country - Irish music - had a particular resonance.

Once we start shooting, it's in there. You're trying to get into a place where you rise to the work, rather than make it manageable or make it work for you.