The Blood Angels strike cruiser Sword of Baal hangs in orbit over the planet Niades, trapped by warp storms. Aboard, the ship's complement of Space Marines chafe at their inaction.
On the trail of their missing Captain, the Blood Angels deploy to the surface of Niades by Drop Pod. Their journey is not a smooth one, and they must regroup to explore the ruined city at the base of the docking tower.
As the Blood Angels on the surface of Niades cut a course through the entrenched Genestealer Cultists towards the signal from Captain Orpheo's beacon, the situation aboard the Sword of Baal goes from bad to worse.
The Blood Angels fight their way ever deeper into the evil that has corrupted the world of Niades, with new and brutal enemies assailing them on all sides. Can their strength hold in the face of such fearsome foes?
Reeling from the brutal onslaught of the Aberrants, Ancaeus and the survivors of his squad must regroup, while Kazarion battles the grip of the Black Rage.
While Ancaeus' surviving warriors follow Castia's Servitors through the under-tunnels of Niades, the Tech-priest explains her plan to the paralysed Captain Orpheo.
The battle for Niades reaches its epic climax as Ancaeus, Kazarion and Orpheo confront the leaders of the Genestealer Cult. Can even the courage of the Sons of Sanguinius hope to overcome the monstrous might of the Patriarch?
In the cult's chambers high up in the Siren Tower, the surviving Blood Angels count the cost of their war with the cult. They are soon joined by Magos Dominus Castia-Theta-9, who offers them a chance to escape Niades.
