I get plenty of time to re-engage with the world I'm trying to depict, so I'm not always living in these parallel worlds.

You're playing a character in a drama who happens to be based on someone who existed. It's never going to 'be' that person, but it's based on someone well-known, and you want to create enough of that person for it not to be a distraction.

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 are far more good actors than there are jobs for them, so it's a big question of luck.

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.

If you ever have the good fortune to meet Tippi Hedren, she's an amazing woman. You can't quite believe she is the age she is.

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.