It is the 42nd Millennium. For more than a hundred centuries the God-Emperor has sat immobile upon the Golden Throne of Terra. He is the master of mankind by right of his own indomitable will, the lord of a million worlds by the might of his inexhaustible armies, and guardian of humanity's future by virtue of his unfailing wisdom and foresight. He is a God to whom a trillion prayers are uttered every second. He is a rotting carcass, writhing invisibly with power from the Dark Age of Technology. He is the Carrion Lord of the Imperium to whom a thousand souls are sacrificed every day, so that he may never truly die. Yet even in this deathless state, the Emperor continues his eternal vigil. Mighty Imperial battlefleets cross the dreadful miasma of the Immaterium, the only route between distant stars, their way lit by the Astronomican, the psychic manifestation of the Emperor's will. Vast armies give battle in his name on countless worlds. Greatest amongst his soldiers are the Adeptus Astartes, the Space Marines, bio-engineered super-warriors. Their comrades in arms are legion; the inexhaustible armies of the Imperial Guard and countless planetary defence forces, the unflinching enforcers of the Adeptus Arbites, the ever-vigilant Inquisition, and the tech-priests of the Adeptus Mechanicus to name but a few. But for all their multitudes, they are barely enough to hold off the ever-present threat from aliens, heretics, mutants, witches – and worse. To be a man in such times is to be one amongst untold billions. It is to live in the cruellest and most bloody regime imaginable. Forget the power of technology and science, for so much has been forgotten, never to be re-learned. Forget the promise of progress and understanding, for there is no peace amongst the stars, only an eternity of carnage and slaughter, and the laughter of thirsting gods...