Dark Heresy: The Corruption Within
In the 41st Millennium, there is only WAR!
In the never ending battles between Mankind and those who would dare to defy their Manifest Destiny handed down to them by their God-Emperor Himself to rule all of the Universe, there exists fights between the Imperium and the Xenos, the denizens of Chaos and the never ending, always growing threat of the heretical witches. Without the dedication of the Holy Orders of the Imperium, Mankind would surely fall prey to itself and be destroyed by aliens and chaos.
Chaos is everywhere. Its sweet words of corruption whisper in the ears of the hundreds of billions of citizens on the planets in the Imperium. Psykers, witches and worse call upon the dangerous powers of the Warp, their souls acting as beacons calling forth the dangers of Chaos and daemons. Weak in willpower, of soul and, most importantly, of Faith in the Emperor, these heretics bring forth nothing less than total destruction of those around them whether their taint is purged from the world or not.
This is where you come in, Acolyte. You have been chosen to act as my ears and eyes to the world. You will fight representing myself, Inquisitor Zarkov Adrastea of the Orodos Hereticus. You will also be a representative of the most Holy Inquisition, hosted by the Emperor Himself. If the Ecclesiarchy is the shepherd of the children of the Emperor, then the Inquisition is the hound who protects the flock from the dangers set to tear them to pieces. They are the Right Hand of the Emperor. We are the Left. Together, we act to gather the flocks of Mankind to the warm embrace of the Emperor. You, Acolytes, you are unproven young pups, torn from the bitch’s teat and cast into the flocks. Root out the wolves in sheep-clothing. Purge the heretic, burn the witch, condemn the unproven psykers. They have turned from the Emperor, but the Emperor has not turned from them (should they still have a soul). Return them to the Emperor’s forgiving embrace that can only be achieved through purifying death.
After all, the Emperor only asks that you Obey Him and Hate those who are the enemies of Mankind.