The Inquisition moves amongst mankind like an avenging shadow, striking down the enemies of humanity with uncompromising ruthlessness. When he finally corners an old foe, Inquisitor Gregor Eisenhorn is drawn into a sinister conspiracy. As events unfold and he gathers allies - and enemies - Eisenhorn faces a vast interstellar cabal and the dark power of daemons, all racing to recover an arcane text of abominable power: an ancient tome known as the Necroteuch.

Horus is dead. Terra lies in ruins. Amid the rubble of the Palace, shell-shocked survivors emerge into the light of an uncertain dawn. New powers are present now, ones that have travelled the length of the galaxy to bring salvation to the Imperium, though they are as readily cast as usurpers as redeemers. The survivors of the Traitors’ Grand Armada, now scattered and desperate to escape vengeance, are riven with doubt and dissension, and their gods too are silent. Amid all the grief and confusion, some hopeful souls believe the war to be over and an era of renewal just ahead.

A great darkness has befallen the galaxy, and the armies of Chaos are rampant. To survive, humanity must retaliate and take back what they have lost. By the will of the reborn primarch, Roboute Guilliman, is the Indomitus Crusade launched - a military undertaking that eclipses all others in known history. From the Throneworld of Terra does the Avenging Son hurl his fleets, their mission the very salvation of mankind.

For Ianthe, war is all too familiar. A former soldier in the Astra Militarum, she now serves Inquisitor Covenant as an agent of the Throne. Her first mission sees her investigating a cult called the Children of Eternity. Falling foul of the local Enforcers, Ianthe soon learns that war in the shadows is seldom straightforward and that the local, angry law-keepers are the least of her troubles.

Before the being called the Emperor revealed himself, before the rise of the aeldari, before the necrontyr traded their flesh for immortal metal, the world was born in violence. Even when they inhabited bodies of flesh, Trazyn the Infinite and Orikan the Diviner were polar opposites. Trazyn, a collector of historical oddities, presides over a gallery full of the most dangerous artefacts - and people - of the galactic past. Orikan, a chronomancer without peer, draws zodiacs that predict and manipulate the future.