Project XII didn't achieve the desired affect. What was meant to be a brain-power enhancer turned out to be quite the opposite; reducing the 'subjects' intelligence to that of an infant and greatly damaging cells, particularly the skin cells giving them an 'off' colour, Project XII proved to be a failure, just like its predecessors.
Unfortunately, Project XII never reached the the secure laboratory that was issued to file the chemical away never to be seen again. Instead another smaller laboratory gain possession of Project XII and underestimated its capabilities.
The pandemic costed millions of lives, with small pockets of survivors gradually emerging. The source of Project XII must be destroyed. Man must eliminate Project XII before Project XII eliminates man...
Made for the Zombie Apocalypse Contest over at the LCN. Whether it's prize-winning material I doubt it, but I was pleased with it and it was nice to build something that isn't war-orientated for a change :)