Goodreads asked M.D. Archer:

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

M.D. Archer Narcissism alert - it came from things I noticed about myself. I have a keen sense of smell, a warm body temperature, I'm sensitive to my surroundings (and sometimes it's as if I know what people are thinking), and one day I had this cut on my leg that healed really quickly.... which led to me thinking... what if there was a species that had all these enhanced senses and abilities but looked normal, and so they just walked around our normal world but had this kind of secret life. The story grew from there.

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