[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.

The important bit for an actor is the actual shooting of it, because the minute the shoot ends, it's got nothing to do with you anymore.

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.

I got sent the script [ Before I Go To Sleep] as usually happens and you have a little look. I know it's a bit of a cliché, but it was absolutely a page turner. I mean, I wanted to find out what happened next.

I had this extraordinarily bizarre moment when, two Fridays ago, my missus gave birth to our second child at 11am and by the same time the following day I was sitting around a table with Ridley Scott, Russell Crowe and Leonardo DiCaprio in Rabat in Morocco, rehearsing a scene we were going to shoot the next day.

Part of me was fascinated by the idea that I would only get next week's episode a week in advance and wouldn't actually know where I was going with it, until the script landed on my mat. But, part of me wanted to know what was going to happen.

I have an enormous amount of respect for Nicole Kidman. She's just done so many great movies and she's been out there at the forefront of carrying films and being a movie star. On set, it really pays dividends because when you're performing with her, she knows exactly how to play it. You don't have to compensate for her in any way.