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.

After seven long years of conflict, the Horus Heresy nears its end. But now, as the Warmaster Horus marches on Terra to rip his father from the Throne, the seat of the arch-traitor’s power lies empty. Cthonia, a world once dominated by brutal murder-gangs, is occupied by the Emperor’s praetorians—the indomitable Imperial Fists. For the Sons of Horus, this outrage demands a reckoning.

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.

When the world of Armageddon is attacked by orks, the Black Templars Space Marine Chapter are amongst those sent to liberate it. Chaplain Grimaldus and a band of Black Templars are charged with the defence of Hive Helsreach from the xenos invaders in one of the many battle zones. But as the orks' numbers grow and the Space Marines' numbers dwindle, Grimaldus faces a desperate last stand in an Imperial temple.

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.

The Night Lords were once among the most potent forces of the Imperium, Space Marines who used fear itself as their weapon. Now, cast adrift from the Emperor's light and hunted as heretics after their monstrous betrayal, the Night Lords clad themselves in symbols of death and fight the Long War, bringing pain and terror to all who worship the corpse-god of Terra. A summons from Warmaster Abaddon sends these rebels on a dangerous journey that leads inexorably to a conflict with the Emperor's chosen warriors, the Blood Angels.

He is known by many names - Clonelord, Manflayer, Primogenitor. He is the epitome of deceit and perversion, and feared by man and monster alike. Once the Chief Apothecary of the Emperor's Children, the madman known as Fabius Bile possesses a knowledge of genetic manipulation second to none.

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.

The Cadian Gate is broken, and the Imperium is riven in two. The might of the Traitor Legions, kept shackled for millennia behind walls of iron and sorcery, has been unleashed on a darkening galaxy. Among those seeking vengeance on the Corpse Emperor’s faltering realm are the Death Guard, once proud crusaders of the Legiones Astartes, now debased creatures of terror and contagion.

After fleeing the authorities in the Imperial city of Altdorf, Felix Jaeger swears a drunken oath to dour dwarf Gotrek Gurnisson to record his death saga. In the cold light of day, Felix's worst fears are confirmed as he learns that Gotrek is a Trollslayer - a dwarf doomed to seek out a heroic death in battle to atone for an unknown personal disgrace. Their travels throw them into a string of extraordinary adventures as Felix tries to survive his companion's destiny.

The Blood Angels Chapter of Space Marines is under threat. Having obliterated all human life in the Red Scar region of space, the largest tendril of Hivefleet Leviathan ever seen in the Imperium has converged and is making relentlessly for Baal. To face this awesome foe, Commander Dante has called upon the Successor Chapters of the ancient Ninth Legion. The Sons of Sanguinius gather in numbers not seen since the dark days of the Horus Heresy.

Dumped on a nowhere world by the opening of the Cicatrix Maledictum, the Red Sunz Mek mob are struggling to survive. When a call to Waaagh! rings out across the planet, the chance at survival, as well as some shooty-fun, beckons. But all is not what it seems. Only an ork with real orky know-wots can hope to overcome the False Waaagh...!

Ufthak Blackhawk and the green tide descend upon Hephaesto - an Adeptus Mechanicus forge world bristling with loot - only to find it already under siege by the notorious Freebooter Kaptin Badrukk. When his warboss, Da Biggest Big Mek, orders temporary co-operation, Ufthak seeks to make a name for himself by crushing some of the Imperium’s most advanced defenders and claiming the greatest prize.

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?

Packed with slaughter and swordplay, these audio dramas, written by Black Library authors including Gav Thorpe, James Swallow, Ben Counter and more, offer fresh insight into two of the Imperium's most beloved fighting forces.