A commission and an original are two different things, and both have their virtues and vices. A commission is a bit more collaborative, in that you outline the story that you think should be told, and then you write it.

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.

I visited the set [of Allied] a few times, and it was a great set to visit. A lot of it was in West London, in an old Gillette factory. You'd go into the factory through the security, and then there were a lot of camels and goats. Most sets are really dull, but this was fantastic.

I think that it's not a bad thing to not be too versed in the vocabulary of cinema, because you start to think that certain things are allowed and not allowed.

I find the best way to make things real is to just put two characters into a space and let them talk to each other in the way that they would talk to each other, and then see what they would say. I know it sounds weird, but that leads the plot and takes you in another direction.

When you're watching, I find two things happen. You either watch a film and it's really good and then you think, "Why can't I do that?" Or you watch a film and it's not good, and you think, "Why am I doing this?" So either way, it feels like being at work.

Sometimes you take something because it's an offer and it's big and it's good money and you have to absolutely respect that process, because it's not easier.