I'd known plenty of people who'd worked with Cillian [Murphy], and he was one of those people I'd only heard good things about. It's pleasing when it works like this. As Cillian said, it's not always like that.

It's a tiny industry. Actors all know each other to a point where you always know someone who knows the other person who worked with them.

It's funny when you know you're playing two characters and you're aware of how you have to play each one into your performance of the other. You're constantly at the back of your mind thinking and it all gets a bit confusing.

I think you only watch stuff you've done once because I don't think it's that beneficial to you. I think it's important to sometimes be like, 'What's that thing I'm doing with my face? I didn't think I was doing that.'

I’m not saying we had a playroom, but I’m not shocked by the sex in the book. It’s essential to tell the story. I can’t believe films that don’t invoke a sexual side of it. So it works for me.

I'm probably the worst person for 'Men's Health' to interview.

I’d been auditioning for parts for years, I never got any better at it. I’m crap at auditions.