It seems like EVERY big sci-fi/fantasy property is getting an adaptation these days, so why not WH40K?
While humanity’s armies wage unending war across a million battlefields, in the darkness, a secret conflict rages – fought by the agents of the Imperial Inquisition. Drawing from sci-fi, fantasy and crime genres, Eisenhorn will see Inquisitor Gregor Eisenhorn and his band of investigators fight to thwart the monstrous schemes of aliens, heretics and daemons before mankind’s doom is sealed.
Inquisitor Gregor Eisenhorn is an Imperial inquisitor, one of the tireless defenders of humanity. With his warband he scourges the galaxy, walking in the shadows of darkness in order to root out heresy. When that heresy is found to infiltrate the hierarchy of the Imperium and the Inquisition itself, Eisenhorn must rely on himself alone to deal with it – even if it means making deals with the enemy and compromising everything he has ever believed in.
I confess that I've never been big into the Warhammer lore, but the people who are into it seem way into it in ways that make them seem like they'd be tough to please. I have a feeling that a fanbase as details-oriented as miniatures fans are will be excited about this but might also wind up being one of the more snipe-y about the plot if everything isn't just right. Still, as someone who's orbited the WH storyline from a distance (there's a lot to take in), I'm hoping this is a good entryway to the fiction.