I understand from those who adore him, he [Julian Assange] has a great sense of humor which rarely gets an airing because he's dealing with such serious issues.

It was great. I got to hang out with him [Martin Freeman as Bilbo Baggins], and I kept a straight face for a bit and then I started giggling because I know Martin, I don't know Bilbo. For Martin to be sitting there playing Bilbo is amazing. He's going to be amazing, he's going to be fantastic in this film.

Only when Stephen Strange has his accident and everything that he's ever had in his life falls apart that he becomes pretty monstrous. It's the self-loathing rage of a wounded animal and he doesn't have a coping mechanism at all. It ties in with the discipline and the magic of this world.

I think it's fair to say that, yeah, I'm playing Doctor Strange, I get there.

It's an interesting arc. You start with a character [Doctor Strange] who's likeable and charming but very arrogant and distant. He's funny but you can see there are massive holes in his life. It's a very painful transition and all that he becomes is tested so quickly and violently.

There's another weight of us being in the public eye, which is this presumption that, because your work and your promotion work is very public, your private life should be, too.

Animations are really powerful - it's not just entertainment, it's a very cunning way to get good ideas across.