Snoop [Dog] said [Peaky Blinders] reminded him of how he got involved with gang culture. It's always fantastically flattering when I see people dress like that and take on the look.

With any period piece I think the thing to do is forget that it's not contemporary when you're writing and to have the characters feel as much as possible like characters that you would know.

Just the idea that someone is married and they've got a kid, and he reports for work one morning and his boss says, "You're wife is a spy. Shoot her." In the real story, he just went back and did it, which would have been a short film. Therefore, I had to spend some time exploring what you would do.

I think that helps because there has been no formality of friendship, the politeness of friendship, so we can just work directly on the work that's ahead of us [with Tom Hardey].

It has to be an actress like Marion Cotillard [in Allied] because there are so many levels to it. It's set in the Second World War, when lots of people were doing things that, outside of a war, you wouldn't do, like killing and dropping bombs. She's doing things that one wouldn't approve of, but it's war.

It was great fun to do because of the central character. With The Girl in the Spider's Web, the girl is really the central character. She's the whole thing.

I think people are drawn to characters that break the rules. I think there is something about a good person doing bad things for what they consider to be a good reason. Then the battle is on to almost prove to the audience that it's justified. How far can you go with that? How far can that character go before people won't accept it? Trying to walk to edge of that line is a challenge.