Daryl Gregory blends psychology and demonology in his dark fantasy debut, Pandemonium.

Previously, you’ve published novellas and short stories. Did you originally envision Pandemonium as a shorter work?

I knew immediately that Pandemonium was a novel-sized idea, and that my writing process would have to change to match the demands of the book. I didn’t begin until I had the ending in my pocket. I didn’t know much about the middle of the book, but once I knew where I was going, I just kept my head down, kept writing and trusted that the elements of the story would come to me as I needed them.

There is an aura of mystery throughout the novel, and it contains a blend of elements from many different genres. What inspired you?

Pandemonium is a mashup of some of my favorite genres, from mystery and horror to classic science fiction and superhero comics, set in a world that’s just one twist from our own. If some weird disease that looked like demonic possession was occurring to us today, we wouldn’t be able to agree on what was causing it, or what it meant. Priests, neuroscientists, psychologists, crackpots and everyone in between would be wondering what kind of story we were living through—fantasy, science fiction or horror.

Your characters spend time discussing archetypes of demonic possession. What kinds of research did you do for this?

I read a great deal about Carl Jung—a man whose life was as strange as anything I’ve found in fiction—and about archetypes and the collective unconscious. But at the same time, I was reading a tremendous amount about neuroscience and the nature of consciousness, the varieties of religious experience and Philip K. Dick’s Valis novels. All of it seemed to be about the same thing: story. Ordinary people get swept up by the feeling that they have a role to play in some greater story.

What were the origins of your unique demons?

My idea was that any archetypes appearing in America would clothe themselves in our pop culture—America’s collective unconscious. I drew on my favorite icons from comic books, pulp fiction and Lovecraftian horror, with a few elements from American myth. The book is my love letter to everything I grew up reading.

Is the story of this alternate world complete?

In the final pages I nudge open the door to show a glimpse of the strangeness to come. There’s always the next weird thing around the corner.