Hitchcock is a big ask. I am playing someone significantly older than me and someone significantly bigger than me. The stuff I find very interesting is why certain physical things have come about. How can he be light on his feet when he is so big? How can his weight vary so much? Where does this rather beautiful voice come from?

There's not a huge pile of scripts at home. It's what happens to be on the table at that moment with your availability. And then you have no control over when these things come out.

I still don't feel I know Hitchcock at all. I find that the more one looks, the more elusive he becomes. But my admiration for Hitchcock the filmmaker remains undiminished. He is a giant of the cinema and the darkness in him informs his cinematic language. You can't separate one from the other.

There are things that I would avoid, so I have the choice to say no, when I feel I'm repeating myself too much. But then there could be a reason to do that with a good director. So I think actors have to have a loose philosophy.

What happens is some of the characters I've played have voices that are so different from my own, that it would be ridiculous if I would dip in and out of that voice in between takes to ask for a coffee, or something. Or to gossip about whatever was going on.

I've got to tell you, I've played real characters before and people always bring up this word 'impersonation,' and I'm never entirely sure what it means.

Particularly [Alfred] Hitchcock, who takes his time with everything he says. There's a controlling way in how he speaks because he takes his time to finish all his sentences.