All of these red carpet events may seem natural for you journalists, but it doesn't feel natural for actors.

I had to change the shape of my own voice. It was quite hard to pull off and so once I had it, I stayed in Hitchcock's voice all day on set.

Certainly for my father, there were great times, good times, not-so-good times. He might be shooting a Fellini film for six months, then not working for two months. I'm used to that dynamic.

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.

When you're training as an actor, a lot of the big work you're learning is to treat fictional characters like real people. You don't have the problem of discovering a backstory with real people, but there's always a mystery which is common to both fictional and factual characters. They are never quite the person you think they are.

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?

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.