What intrigued you most about the story of Katharine Gun? originally appeared on Quora, the place to gain and share knowledge, empowering people to learn from others and better understand the world. You can follow Quora on Twitter, Facebook, and Google Plus.

Oddly, what initially intrigued me about the story of Katharine Gun was that I hadn’t heard of Katharine until my producer Ged Doherty (with whom I’d made Eye in the Sky) called me one day and asked if I knew who Katharine Gun was. I said I didn’t. He said, “Google her and call me back.”

Two hours later I called him and said, “How come her story isn’t better known? It reveals so much about how we were lied into the 2003 war in Iraq and it poses really intriguing questions about loyalty: Loyalty to conscience, to marriage, to government, to country.

Subsequently I spent many days interviewing Katharine. And, as I got to know her, I realized what really intrigued me was the question her story compelled me to ask myself. Would I have the courage to do what she did? If tested, where would my loyalty lie?

I was intrigued that Katharine was actually quite an ordinary young woman. She went to work every day like most of us do, and one day something landed in her email that revealed something was happening in her organization that was simply - wrong. So, for me, the intriguing question her story raises is whether any of us would have the courage to speak up if we found some kind of corruption or immoral behavior going on at our place of work? Or would we just keep our mouths shut? Would we have the courage to risk losing our jobs to expose illegality or immorality or exploitation? Of course Katharine risked not only losing her job but also her freedom. That intrigued me.

Working with a cast of great actors is a director’s dream. I was exceptionally lucky to be able to make the film with very talented stars like Keira Knightly, Matt Smith, Mathew Goode, Rhys Ifans and Ralph Fiennes. But I also want to mention the many supporting cast members in the film. Acting is a game of tennis. You can’t play a great game if the person you are hitting back and forth with keeps missing the ball. So, for me, the unsung heroes of good movies are the cast members who play the many supporting roles. If great acting is great reacting, then the leads need great supporting actors to react off of. I firmly believe that every role matters. When the camera is on the face of an actor they are, for that moment, carrying the film. If an actor in a minor role drops the ball, they drop the audience - and the suspension of disbelief is broken for a moment and has to be rebuilt. Drop the acting ball too many times and you have a bad movie. Too many false notes in small roles and even great leads can’t pull the audience back in. So I like to audition and audition until even the smallest role is cast with an actor who can light up a screen and hold a moment. When you ask how it was to work with the cast I know you probably want me to tell you how great all the leads are. And they are truly great. But I also really enjoy the process of working with my casting director during preproduction to build a full cast that will all deliver great performances.

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