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.

Born into riches, Probator Symeon Noctis attempts to atone for his past sins by championing the powerless of Nearsteel district. But the sprawling city of Varangantua is uncaring of its masses, and when a bisected corpse is discovered in the neutral zone between Nearsteel and the Adeptus Mechanicus enclave of Steelmound, Noctis finds himself cast into his most dangerous case yet.

Belisarius Cawl, Archmagos Dominus of the Adeptus Mechanicus, is the most brilliant mind alive. For 10,000 years he has furthered the cause of mankind, working under the aegis of the Emperor and Lord Commander Roboute Guilliman to prevent the inexorable march of the alien and the traitor. Many call him heretic, but all must recognise the magnitude of his achievements, for who else but he was entrusted to create a new generation of Space Marines?

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.

Follow the exploits of Oltyx, who, having finally been granted the throne of the Ithakas Dynasty, now faces far greater threats, from within and without. He soon learns that the lessons of kingship are not quite what he had hoped.