The Inquisition is the most powerful organisation of the Imperium’s many branches. Its agents, the Inquisitors, command fear and respect in equal measure. They are creatures of myth as much as flesh and blood, relentless beings who descend from on high to pass judgment upon the mutant, the traitor and the heretic. Known as a man of steely resolve and purity of willpower, Gregor Eisenhorn is a legendary Inquisitor, who in his career has moved from the ideology of the Puritan to that of the Radical – a journey which has led to accusations of heresy more than once, though Eisenhorn has always proved himself to be naught but righteous. Those who have crossed Eisenhorn’s path and lived are seldom eager to invite his attention again.