There are very few well-adjusted people in my books. But I do think that's normal. Because everyone does have their issues and hang-ups.

I was working as a secretary in Manchester and thought I would always do that. Then I got this letter offering me a two-year fellowship where I could write; they would pay me a salary and give me a flat to live in. It was heaven.

My favourite Friday treat is to drive out of the centre of Cambridge, where we live, and go for a swim at the health club I've just joined out in the countryside at Quy. It's a lovely pool, inside a converted barn. Usually it's just me and a couple of other swimmers there.

I'm snobby about books that aren't crime fiction: if I start reading a literary novel and there's no mystery emerging in the first few pages, I'm like, 'Gah, this obviously isn't a proper book. Why would I want to carry on reading it?'

Agatha Christie's writing is incredibly skillful because her books are incredibly intellectually puzzling and challenging.