Q: Where did the idea of the story come from?
A: We used to live in mid-Wales and the Elan Valley was one of my favourite places, wild, remote, but with reservoirs as beautiful as anything in the Lake District. I wanted to celebrate the achievement of the dams, and the beauty of the landscape, in some way.
Q: How much of the story is true?
A: All of the facts, everything about the building of the dams, are correct. But the plot, the characters, and some of the geography, are all made up. No historical figures, no one real, appears in the book: there is no Cuckoo’s Nest, or the farms I describe: and there was no embezzlement I’m aware of, certainly no murders like the one I describe. The plot is basically a means of exploring the history.
Q: Why did you decide to make your detective English and not Welsh?
A: I felt he had to be an outsider, so that we, as readers, can learn about things through his eyes. And some of the stories of Wilkie Collins, for example, feature London detectives who’ve been hired to solve a local case.
Q: Why have you decided to switch from fantasy to mystery fiction?
A: I wrote the first draft of the book in 2003, in fact it was my second novel, before I really knew what sort of writer I wanted to be. And I thought the story was complete in itself, it didn’t need any fantasy elements to make it work: in this instance, fantasy would have got in the way. And besides, all my books are mysteries in one way or another.
Q: How has the book changed from the first draft?
A: It’s a lot shorter! The first draft was a bloated 130,000 words. In the decade since I’ve put it on a rigorous exercise regime and got it down to a trim 76,000 words. But everything else, the plot and characters, hasn’t changed. It was just too wordy.
Q: Will there be a sequel?
A: I wrote it as a one-off, and certainly I don’t plan to write a series, like Inspector Morse or Hercule Poirot. But if the book sells, if there’s a demand, I may write a sequel, yes. I have a few ideas about a murder in the fishing industry up in Wick that might need investigating: I mean, have you seen those gutters use their knives…?