Where did you get the idea for your most recent book?
I write a lot of books at once, but I'll tell you about The Emperor's Railroad, which is out in April. I've been watching the Walking Dead. I love it, but one thing bugs me about it - some simple armour would make everyone in that series a lot safer. I made some chainmail myself when I was a kid out of cut up fence wire. That had me thinking about knights versus zombies, basically. And that in turn led me to thinking about the realities of a zombie apocalypse. Eventually, the zombies would fall apart and there would be too few living people left to replenish their numbers, so after an initial population crash, civilisation could begin to recover. That then led into me daydreaming of a world a long time after a zombie apocalype, which in turn had me trying to come up with a plausible explanation for zombies. Thinking on their origins, I began to add in lots of other stuff that I like about post-apocalyptic fiction, especially the weirder stuff. So there are bits and bobs taken from other fiction and science, all stitched into the story. It's quite magical how one simple idea can be the germ for an entire world, and it's one of the things I love the most about my job.