How galling to watch someone who looks like you, who basically is you, do all the shagging you didn't get to do.

All roads seem to have come back to Doctor Who in our life. But, no, it was a huge part of my growing up. I was a massive fan and it certainly inspired me to get into acting and to be ... one of those people that tells stories on TV. That was a huge part of my childhood.

Getting the call to be in The Goblet of Fire was like being welcomed into the most exclusive upper circle of some elite actors' club. You sit on set with the cream of the National Theatre and the RSC, all clutching wands or wearing witches' hats.

I'm a good person, I hope. But I'm never as good as I want to be, never as nice as I want to be, never as generous as I want to be.

If you speak in a different accent, you begin to move in a slightly different way. You think in a slightly different way. It's part of trying to find what makes a character.

And the very fact of how you speak somehow influences who you are. The way you move, the way you think, it seeps into your being, and it's quite hard to really break that down entirely.

It's very hard to be objective about something you're in, especially when you set it up against things that you experienced as a child.