Daemons have come to the world of Arboria, and with them, death. The Ultramarines have deployed to stem the tide, but they must do so quickly, for if they fail, the sinister agents of the Inquisition will enact Exterminatus upon the devastated world, destroying it utterly at the loss of millions of lives. As Sergeant Cerrano and his Scouts battle to protect the remaining civilians, the representatives of the Inquisition arrive...