So, some of you are probably wondering how a novella like Equoid gets written.
A man walks into a bar.
Actually, two men walk into a hotel bar in downtown Denver, during the world science fiction convention. Charlie Stross is sitting in the bar, nursing a beer between events, and vaguely thinking about tracking down Peter Watts. But his attention is captured instantly as he notices something very odd about the two mens' body language.
One of them is John Scalzi. His body language is exuberant, extroverted, salesman-like. The other is noted editor Lou Anders. Lou's posture is defensive, arms crossed, cheek turned—almost as if he's biting back the words, get away from me, you creep!
Charlie has had a couple of beers and is feeling mischievous. So he gets up and approaches Lou and John. "Hi, guys," he says, "What's the argument about?"
"I'm trying to sell him a theme anthology!" Says Scalzi.
"But I'm not buying it," Says Anders.
"What's the theme?" Asks Stross.
"It's about unicorns!" Scalzi is bouncing up and down, almost vibrating with enthusiasm at this point.
"Unicorns?" Stross asks: "Surely there's got to be a new angle ...?"
"Yes! It's going to be a theme anthology of Unicorn Bukkake stories!"
Stross does a double-take as a light bulb—well, actually a stadium-sized floodlight—snaps on above his head and the hideous concept of unicorn bukake instantaneously cross-fertilizes with the sexually dimorphic marine predator he was wanting to ask Peter Watts about, and inseminates the Laundry Files universe.
"Lou, if you publish John's anthology I'll contribute a story: will that help? I've just had this idea ..."
Stross explains his idea about the life cycle of unicorns to Scalzi and Anders. When he stops retching, Scalzi's body language changes until it eerily matches Anders.
"Don't call us, we'll call you," he says with icy-sober politeness, and beats a hasty retreat.
That was in 2008.
Once the idea of unicorns as a sexually dimorphic species like unto ceratioid angler fish dug its way into my mind, I then began thinking about other aspects of the bizarre parasitic life-cycle of the unicorn. Mimicry is part of it. Co-opting a host to provide shelter and food is another. Having a distinct motile juvenile phase and a sessile spawning phase gave me a great explanation for some of the more disturbing aspects of unicorn reproduction. (Yes, I ran the Equoid life-cycle past Peter Watts for comment.)
Of course, the Equoid had other fortuitous side-effects for the Laundry universe: everything came together very neatly. The unfertilized juvenile female obviously provided an explanation for the pervasive mythology of the flesh-eating horse. And the adult, sessile, spawning horror lent itself to a particular interpretation of H. P. Lovecraft's nervous breakdown of 1908. Oh, and finally this allowed me to demonstrate the precise relationship between old HPL's mythos and the Laundry universe—namely that HPL is an enthusiastic but inaccurate guide, and about as much use to a practicing demonologist like Bob as a copy of the Anarchists Cookbook (the recipes in which are infamous for reducing the population of aspiring anarchist cooks).
All I needed then was a story. So I wrote about the first 4000 words in 2008, and let it settle for a year. Then wrote another 2000 words. Then had to put it away to make way for a novel. Or two. Or three. Finally, in early 2013, I had a gap—I'd just finished writing "The Rhesus Chart" and needed something to chew on. And it occurred to me that now was the best time to nail the sucker down, so I sat down in March and wrote the other 27,000 words of "Equoid" in about three weeks.
But anyway, I thought I'd give you this account of the origins of "Equoid", just so that Anders and Scalzi can take their fair share of the blame. Cheers, guys, and next time John pitches a theme anthology you'd better invite me!