Suddenly, after years of television being the poor relation and film being everything, it now feels like film is a conjuring trick. It's like, "Oh, my god, how are you going to do that in 90 minutes, as opposed to eight hours?! I've got so little time to do this!" It becomes an art form, in itself. Doing both helps you do each one.

I'm very, very excited because I'm just completing Episode 6 of Series 4 [of Peaky Blinders], which again I think is the best yet. And I'm loving it and it's not like work, it's not like a labor, I love doing it, and the boys are coming back and they're loving the scripts.

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.

I've been writing so much. And what happens with TV is that they split [Taboo] into two blocks, so you get a director that does four and another director that does another four. You commit yourself to seven days a week, for 12 or 13 hour days for a long time. I couldn't really do that.

You know that when you suggest something on the page, it's going to be there, plus more. It's a great luxury to know that you don't have to push it. You just lay it out, and it will be there.

The time came where I was able to write an original screenplay [Allied], and it would be read and noticed. I had a meeting with Brad [Pitt], just around the time that he was making World War Z. I basically told him the story and said, "This is what I want to do," and he really responded, so that helped me put the thing together and write it.

[Taboo] has been exactly the same as working with the BBC in that creatively they do that precious thing which is to only make a comment when a comment needs to be made.