The biggest challenge was to make sure that we are looking at things honestly and truthfully. We weren't making an apologist film. That was the toughest part.

It's so easy to say "evil Nazi monsters," but as soon as we do that, we take away the fact that it was individuals committing individual acts of murder. They had children, and what does that do? As soon as you generalize, they become monsters. It doesn't allow you to understand it in any kind of sophisticated way.

I studied fascism when I was at university. My husband's family are German Jews. I'm very close to his grandma and she left Berlin when she was 19 in 1937. So, it's kind of all around me.

Try and withhold your judgment, because as soon as you think you know something, you're shutting down.

Every film you do, you always look at it and you think, "I could do better," but I'm never going to tell people what I could do better. I think it's up to them to make up their own mind.

I'm a really judgmental person, and it just dumbs everything down. It doesn't create any room for interrogation or investigation.

I feel like I need just to keep trying to make the work for the right reasons. I think part of that is working with really good people, and just trying to make strong truthful work. And not being diverted from that.