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.

If you have an over-preoccupation with perception and trying to please people's expectations, then you can go mad.

Even though my parents experiences were different from mine. I wasn't a child actor brat; I didn't travel with them in the circuit. But I got a look into their world, so I did know what I was getting into, to an extent. And they are a constant source of grounding.

The armoury of having any academic education does not necessarily set you up for being a good or better actor.

I've been very lucky at what's happened in my career to date, but playing something as far from me as possible is an ambition of mine - anything from a mutated baddy in a comic book action thriller, to a detective. If anything, I'd like Gary Oldman's career: he's the perfect example of it. I've love to have a really broad sweep of characters - to be able to do something edgy, surprising and unfashionable.

My own grandfathers were a submarine commander and a 'desert rats' tank operator in the Second World War.

I've never been front and centre as an iconic American character [like in Doctor Strange]. Day to day, you know you're painting on a very big canvas.