[Role of Dr.Strange] gives me an excuse as an actor to be learning with my character, which is something you can do authentically - I'm not a martial arts expert, I'm certainly no sorcerer, so all these things, the movement of the body, the physicality, the changes he goes through mentally and physically, obviously we're not shooting in sequence, but it's a great part.

There's a huge amount of footage of Julian [ Assange] online, but he's usually in presentation or defending mode, talking about his cause, or the revelations which Wikileaks have brought about. There's none of Assange relaxing or in private mode. There's none of the personality I tried to give him behind closed doors [in The Fifth Estate ].

I've always wanted to play a spy, because it is the ultimate acting exercise. You are never what you seem.

I was brought up in a world of privilege.

Landing the role of Stephen Hawking was the most positively surprising thing that has happened to me.

I love doing impersonations of people.

The first time we did cavalry charge I was so breathless with excitement I nearly fell off the horse. I actually saw stars in front of my eyes and thought I was going to faint. The second time I had a bit more control but was still giddy with excitement. And the third time I was an emotional wreck. I had to really try hard not to cry.