I grew up reading old monster comics and watching the classic black-and-white Universal monster movies, and loving all of them. But it always bugged me a little that they seemed to exist in a world in which there were so many different WAYS to become a monster. Bitten by a werewolf under a full moon, or bitten by a vampire, or cobbled together from a bunch of dead bodies… there was a completely different set of rules at work for every monster, a completely different rationale. But why SHOULD a vampire’s bite turn you into a vampire, and why do vampires crave blood? And, perhaps even more germane for the heroine of iZombie, why do zombies crave brains (which they have at least for the last thirty years or so)?

iZombie began with a brief paragraph-long pitch, that centered entirely on the main character and her personal issues. I didn’t have to spend a lot of time worrying about how her world worked, or the rules of zombies. But when Vertigo editor extraordinaire Shelly Bond asked me to flesh that one paragraph out into a full proposal, I knew I was going to have to work out how that world worked, and how the various monsters worked within it.

I was heading off to a convention that weekend, and so spent the whole flight out furiously scribbling down notes in longhand in a spiral-bound notebook. And when I got to the convention, I used every second I wasn’t on panels or doing signings transferring those scribbled notes over to my laptop, and gradually fleshing them out. And when I was done, I had worked out who each of the supporting characters and antagonists in the series would be, at least in general terms (it wasn’t until Mike Allred signed onboard a few weeks later that many of them came into focus). And more importantly, I worked HOW monsters worked in this world.

I won’t go into TOO much detail about the metaphysics of iZombie, since it would spoil some of the later chapters in the first collection, iZombie Vol. 1: Dead To The World, but the basics are these: everyone has more than one soul, and they don’t always depart with the death of the body. The basic notion is lifted from the beliefs of the ancient Egyptians, but filtered here through the bicameral structure of 20th century psychology, with one soul associated with the conscious mind, and the other with the unconscious. And once I’d worked THAT out, I suddenly knew why vampires craved blood, why zombies craved brains, and why some ghosts seemed charming and personable and others were seemingly mindless shrieking phantoms.

I always like to work out the rules of a world before I get too deep into writing about it, because I find it helps me to know what is and isn’t possible. And the nice thing about working out my own personal “unified theory of monsters” is that it suddenly occurred to me that we could make use of many MORE monsters than we had originally intended. Someday, lord willing and the creek don’t rise, I hope to get a giant mutated kaiju monster into the book (don’t tell Mike and Shelly, though, I’m keeping it a secret). I don’t know why or when we’ll use it, but now that I know the rules of the world, I know exactly HOW we’ll be able to pull it off!

--Chris Roberson