You were born in Britain but have lived in Canada since you were 17. Why the move?

Well, my mother was widowed during World War Two and basically decided to start afresh in Canada because she had a sister there. I had no complaints, as I'd just finished school and Canada seemed to me almost impossibly exotic and fascinating. A brand new world to explore.

Of course, I'd set myself up for a fall. We ended up in a really dull little town where absolutely nothing happened, ever. The polar opposite of exciting. Luckily, I was saved by university, and eventually came to love the country. Which is why I never even considered any other location when I came to write the Murdoch novels.

When did you realise you wanted to be a writer?

Unlike some writers, I had no awakening or epiphany when I grandly declared to myself that I'd be a writer. Instead, I always sort of knew, without actually acknowledging it.

I was an obsessive bookworm as a child and teenager, ploughing through three or four books a week, so I guess on an almost subconscious level I knew my future lay in literature. But I didn't consciously consider it until well into my adulthood. Perhaps because the very idea of writing for a living seems so outlandish – as impossible as changing one's eye colour. It was only after I'd worked in other jobs that I finally picked up the pen and got on with it.

Why did you take 19th Century Toronto as the location for your novels?

Well, I actually started out as a playwright, writing two crime dramas set in the 19th Century. I picked that period as I didn't want to spend all my time researching the latest forensic techniques. The simple solution was to set the plays in the pre-forensic period, when detectives had to make do with big bulky clues and their own wits.

I enjoyed writing the plays so much that I decided to progress to novels, and just thought it made sense to stay in the 19th Century. Toronto was the perfect setting, as I know the place well and it's basically a very Victorian city. It's rather like London in that way – there are epic, old buildings everywhere and you can commune with the ghosts of the past during your daily walks. It's enormously inspiring.

How did you develop the distinctive, rather paradoxical personality of Detective Murdoch?

Well I wanted to create a character that I would find interesting in person – someone I'd want to spend time with in real life. So I gave him a very progressive mindset, making him a man ahead of his time. Yet I also wanted to give him theological leanings, and this actually comes from my own experience. I attended a university that was run by the Basilian Fathers, who are an order of Catholic priests. And while I was there, I got to know a fair few priests and nuns who actually had trouble reconciling their religious beliefs with their modern, secular leanings. I gave some of this conflict to Murdoch.

I was also inspired rather directly by a photograph from the 19th Century – a dashing young man who immediately became the model Murdoch in my mind. Actually, a lot of my ideas stem from old documents. I plundered the Toronto archives for actual coroner's reports from the period, and these helped me put together my plots.

What's your take on the TV series? Does it have the Maureen Jennings stamp of approval?

I actually visited the set a few times and it was an eye-opener. As a writer, you sit there happily making up scenes without a care about costings or practicalities. But then the poor filmmakers come along and have to work out how to bring it to life without bankrupting themselves. It was fascinating to see how they adapted bits of my novels – getting rid of a scene involving fire, for example, as it would be just too expensive. Or changing a scene involving kids as there were no child actors available.

It's all worked amazingly well as far as I'm concerned. And Yannick Bisson is exactly as I imagined Murdoch, apart from one small detail – he doesn't have a moustache. One of these days he should fix one to his upper lip and see how it looks.

Did you grow up reading crime writers? Which ones inspired you the most?

Arthur Conan Doyle was my literary god, and still has a huge influence on me today. In my formative years I also read a lot from the so-called "Golden Age of Detective Fiction" – that's the 1920s and 30s, with writers like Dorothy Sayers and Agatha Christie churning out these satisfyingly formulaic whodunnits. They taught me a lot about plot development and so on, but I read some Sayers recently and just thought "Urgh!"

As for writers around today – I have to say I love Ian Rankin and PD James. How could one not admire PD James in particular – she's in her 80s and still writing brilliant crime novels.