Goodreads asked J.M. Harrison:

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

J.M. Harrison It's a bit of a weird one. I was on holiday (with no plan to write at all) when the creative juices started flowing. I bought a couple of notebooks and wrote down the entire story.
You can read an article about this here:
http://www.authorjmharrison.com/books... just scroll down to read the article on the right hand side of the page.
And here's the trailer: https://www.youtube.com/watch?v=L8l87...

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