Personally, I just want to work on stuff that challenges me, that excites me, and that I think is original. You want to do something that does to other people what films do to you. It's the most wonderful thing in the world when you can lose yourself from reality and go into a story, and believe it and go on that journey with people, and you have to work that will somehow do that. It won't always, but hopefully sometimes.

Weirdly, some of the middle stuff of the descent into something going wrong were the hardest, tonally. You don't want to jump the gun and be instantly paranoid about the fact that she has made coffee wrong because that would be weird. It's the slow build and letting it sink in. If they say everything is okay, you believe your partner. You don't want to rattle the boat too much on your honeymoon.

There's comedy in tragedy, and tragedy in comedy. There's always light and dark in most jobs. Whether it's framed as a comedy, drama or tragedy, you try to mix it up within that. You can work on a comedy and it's not laugh-a-minute off set. You can work on a tragedy that's absolutely hilarious.

The Victorian world is extremely dark and extremely bright.

I think it's amazing to have one writer write every episode of a series. It's very rare, I think. You get a voice that continues.

Tone is always such an important thing, and that's achieved through a multitude of people. It comes through the writing, it comes through the way it's shot, and it comes through the production design and the sound design.

I love playing a character that has more than 90 minutes, and that keeps going.