I often get sent scripts about little men in big situations. There's a comic element to it, which is forces stacked against this little guy, and how is he going to defeat them?

It's always very strange to have your life dramatized because it never happens like that. Things will be different.

They know you're not Alfred Hitchcock, but you need to be enough Alfred Hitchcock for them not to be bothered by it. That's a reassuring thing.

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?

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.

It's hard to imagine anyone interested in film not being a fan of Alfred Hitchcock because he's such a key influence on the entire history of cinema - it's hard to escape his shadow.