After seven years of bitter war, the end has come at last for the conflict known infamously as the Horus Heresy. Terra now lies within the Warmaster’s sights, the Throneworld and the seat of his father’s rule. Horus’ desire is nothing less than the death of the Emperor of Mankind and the utter subjugation of the Imperium. He has become the ascendant vessel of Chaos and amassed a terrible army with which to enact his will and vengeance. But the way to the Throne will be hard as the primarch Rogal Dorn, the Praetorian and protector of Terra, marshals the defences.

Abandoned by his primarch and left to lead the Space Wolves into an uncertain future, Bjorn the Fell-Handed is amongst the greatets of the sons of Russ. But even legends must fall, and when Bjorn meets his end on a distant world, his body broken beyond repair, his brothers battle to save him, and he remembers the events that brought him to this place...and realises his destiny.

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.

The primarchs, nigh-immortal sons of the Emperor of Mankind, take the stage in a series of short stories showcasing some of their great deeds and hideous acts from across the Great Crusade and the Horus Heresy.

In the sprawling Imperium of Mankind, everyone serves the Emperor in their own way. From the inquisitors who hunt the hidden enemies of humanity in the dark places of the galaxy to the brave soldiers who stand on the front line, and the Imperial Assassins who can change the tides of war with a single shot, each has a part to play in preserving the Imperium. In this audio anthology, three of these disparate heroes are put to the test, each facing a personal crisis that will see them either fall to darkness, or rise to continue doing their duty in the Emperor's name.

Blade of Purity contains two linked tales of the Grey Knights: Incorruptible and True Name.

On the forge world of Morod, the machines never stop and the work never ends. The population toils in the mines and factoria to protect humanity from the monsters in the void, while the Adeptus Mechanicus enjoy lives of palatial comfort. Genetor Gammat Triskellian seeks to end this stagnant corruption. When he learns of a twisted congregation operating within the shadows, one which believes that the tech-priests are keeping people from their true salvation, he sees in them an opportunity to bring down Morod's masters and reclaim the world in the name of progress.

Throughout the tortured galaxy, Ephrael Stern is known by many names. The Thrice-born. The Daemonifuge. The Heretic Saint. Trapped deep within Imperium Nihilus following the coming of the Great Rift, the maligned Sister of Battle fears the Imperium is no more. The God-Emperor’s light, which has guided her through centuries of strife, has too extinguished. Seemingly forsaken, Stern is bereft until a mysterious stranger arrives, offering her a new destiny. One that might yet see the Imperium saved. Stern must prove herself worthy of the God-Emperor’s grace once more.

The planet of Theotokos is dying. Drought has wiped out all but the capital city of Magerit. Worse, an outbreak of a terrible plague, known as the Grey Tears, ravages its populace. Only the charismatic Arch-Deacon Ambrose stands in the way of desperation and anarchy. But as the plague rampages through the streets, murdering its victims with unnatural symptoms, Ambrose struggles to confront the appalling measures he must take to save his people.

In the far reaches of Imperial space, a ferocious warp storm approaches an Administratum world, cutting off the entire planet from the rest of the Imperium. As their towering grey spires are punished by endless rain, countless administrators, tithe-masters, and book-keepers are forced to evacuate. Among them is Greta, a lowly data-drone with a terrible secret, wanted for questioning by the sadistic Imperial interrogator Stefan Crucius. As disaster strikes and the pair are left stranded in the depths of the drowning city, captor and captive must cooperate.

In the jungles of Aztlan a deadly war of the shadows is being fought. And the Imperial Guard are losing. The alien t’au, though few in number, greatly outclass the soldiers of the Imperium and are taking a serious toll on their forces. A call for aid is answered by the fearsome Mortifactors Chapter, who come to the world full of grim purpose. Adoni, an unblooded neophyte yet to earn his place, is amongst the war party. As the Mortifactors descend into the jungle vastness, they hunt for a killer, one that will not die easily but that whom Adoni must slay if he is to become part of the Chapter and a Taker of Heads.

The wind screams. The dark night is freezing. Vossk, a Vostroyan Firstborn, shrinks into a rock against a howl of memories. Having disgraced himself by deserting his post during a terrifying encounter, Vossk had resigned himself to penal servitude, though yearned for the chance to redeem himself. But in the 41st Millennium, such dreams are hollow when a man’s reality has been shaken to his core. Found in the shadows of a pitiless cave, Vossk relives his tale to his rescuer....

In the midst of a vast gas nebula lies a remote watch-station, hanging silently against a tapestry of dying stars. It sits alone, patiently awaiting lost travellers adrift in the freezing vastness of the void. To such souls it appears as a blessing, a safe haven from the warp storms that wrack the immaterium and destroy the ships of those foolish enough to test the tides. To Captain Arq and her crew, it is one thing - refuge. But things are never so simple.

On the world of Tevrat, Callidus Assassin Klara Rhasc stalks her prey, awaiting the moment to strike. But when her mark is murdered by a crazed Eversor Assassin, Rhasc embarks on a new kind of mission: to find and subdue her fellow operative.

Travelling across the daemon world of Eidolon in search of the stolen Blade Encarmine, Blood Angels Captain Leonatos and his battle-brothers encounter survivors from the 409th Kadmeian Janissaries regiment of the Imperial Guard.