I think it serves the purpose of the film if the premise is that you're unsure of me because you've only ever really seen me play villains.

Rowan Joffe is very specific. I mean, he wrote it as well and he has a very orderly writer's mind and the same applies to his directing.

And I think in your 40s, you land a little bit, physically and mentally, you arrive at a place where you feel you've learned some stuff. Having children at that point meant I had something very useful to do for the next 20 years.

Because I had children relatively late - in my 40s rather than in my 20s - it wasn't anything I ever knew that I would do. It kind of happened to me: I met the right woman and we had children. It was a revelation because it suddenly makes me realize "Oh, I get it. Now I know what to do with the rest of my life."

When you're making a psychological thriller, what you need to do is have an audience on shifting sand so they're never quite sure where they are.

[Before I Go To Sleep] script was a great journey with all the twists and turns that were kind of unexpected. I had to finish the script, and I thought if we can emulate this in the film, it's going to be a really good film.

Interestingly, this character [Doctor Nash] is probably closer to me than somebody like the evil Sir Godfrey in Robin Hood or Lord Blackwood who wants to take over the world in Sherlock Holmes. This is a character that's English, he's based in London, and so it's closer to me than a lot of stuff I've been doing recently.