Goodreads asked Peter Caulfield:

Where did you get the idea for your most recent book?

Peter Caulfield My past novels (published as Peter Facer) have all been described as "High octane crime thrillers) but I've always had an interest in British history. I love Barbara Erskine's books and the way she weaves the present day and the past into compelling novels. Where hers tend to be more on the supernatural spectrum, I wanted to write something more akin to time travel. As it happens, there's a lot of the supernatural about "Catherine" too.
I can't really explain where the idea came from. I sat at the computer and simply wrote the opening sentence, "The point of the dagger hovered a hair’s breadth above the artery pulsing in her neck." At that point all I knew was that this person was an ancient Briton from the Dark Ages. I write very organically so I had no idea where this story was going until I continued writing.

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