Once upon a time, three mighty orders of the Adeptus Astartes swore together to defend the scattered planets of the Shroud of Elara. Star Scorpios died due to malfunctions in their own gene code. The Heavenly Lions were destroyed by the Inquisition for sins they did not commit. And now, hundreds of years later, the Veil continues to be guarded only by the Spears of the Emperor - savages opposing the Outer Darkness, bloodless, but not broken over many years of service. Amadeus Kaias Inkarius, a brother from the Legion of Mentors, is sent through the Great Rift to ensure the combat readiness of the Spears. But instead he finds himself embroiled in the chaotic and hopeless squabble that is a crusade on the far, dark fringe of the Imperium. The decisions he must make here, far from the light of the God-Emperor, will determine the fate of the war-weary order.