The galaxy is in flames. Chaos is in the ascendant across the stars. The Great Rift has split the holdings of the Imperium in twain, isolating entire sectors from the light of Holy Terra. But all hope is not lost. The Primarch Roboute Guilliman has returned from deathless sleep and appointed Commander Dante, lord of the Blood Angels, as Regent and Warden of the newly dubbed Imperium Nihilus. In the Baal system, the shattered holding of the Chapter is being rebuilt, and Dante plans the greatest campaign of his long life, to retake half an empire. 

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. 

The Ghosts are thrown into a new kind of war, sent into battle on grav-chutes to fight on platforms far above a toxic atmosphere. And the atmosphere in the regiment isn't much better as the feud between Mad Larkin and the really insane Lijah Cuu heats up...and turns deadly.

The shrine world of Divinatus Prime has become lost to the light of the Astronomican, and no ship can piece its veil. Only the Lord of Death himself, Blood Angels Chief Librarian Mephiston, has any hope of discerning the fate of this once pious world. After enacting a powerful blood ritual, Mephiston and an honour guard of his fellow Blood Angels reach the stricken shrine world to find it seized by religious civil war. Each faction fights for dominance of a potent artefact, the Blade Petrific, said to be wrought by the Emperor Himself.  

As the Great Rift tears the galaxy apart, portents and darkness beset Mephiston. At the time when he needs his psychic sight the most, the chief librarian's powers are rendered blind. Haunted by the ghosts of the damned, their purpose unclear, Mephiston takes his ship the Blood Oath and the Blood Angels in his charge to the world of Morsus, where he believes the source of his psychic blindness is to be found. But Morsus is embroiled in conflict too, a longstanding struggle between the Imperium and some of its most ancient foes called the Revenant Crusade. 

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. 

Attached to Crusade Fleet Quintus - dubbed the Cursed Fleet by many - the Ultramarines of the Ithraca’s Vengeance are drawn to a stricken world. With millions enslaved, a malign necron technology siphons the souls of the innocent and heralds the Silent Kingdom’s expansion. The Ultramarines face an impossible decision: mount a desperate last stand to destroy the Pariah Nexus, or break away and damn the entire sector to bring word of this ancient foe’s resurgence to the only being capable of halting it - the Lord Primarch Roboute Guilliman.  

Newly promoted to the captaincy of the Ultramarines Fourth Company, Uriel Ventris leads his warriors to the world of Pavonis, where vicious alien raiders are bringing death and destruction. As Pavonis descends into political turmoil, Uriel and his warriors must battle the xenos as they unravel a plot to unleash an ancient evil buried deep beneath the world - the mysterious and deadly Nightbringer. 

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.

In disgrace after a catastrophic war, Colonel-Commissar Ibram Gaunt and the Tanith First are sent to retrieve precious artefacts from a world lost to Chaos. With enemy all around them and time against them, Gaunt's Ghosts and their allies must prevent the holy relics of Saint Sabbat from falling into their foes' hands, and as mysterious events begin to occur, Gaunt begins to suspect that the Saint herself might be aiding them from beyond the grave. 

Each primarch is an exemplary being, derived from the Emperor’s own genetic stock to embody a facet of His personality. Their powers are unfathomable, but only one of them is the First. Lion El’Jonson is the paragon of what it is to be a primarch. His Legion, pre-eminent for most of their long history, typify the virtues of temperance, pride and martial excellency that the Lion embodies. They are the Emperor’s last line and final sanction. They are His Dark Angels. 

Lieutenant Xedro Farren is a Primaris Marine, stronger and more adept than even the Space Marines his brotherhood is sent to fight alongside. As the Dark Angels and the Primaris Marines fight a trauma-scarred force of T’au hellbent on destroying their former allies, the true quarry becomes clear - the shadowy instigator of a psychic curse that could plunge a string of Imperial planets into madness. As worlds burn in the fires of battle, an unthinkable pact is struck, with the Primaris Marines peeling back layer after layer of deceit to find the appalling truth. 

As Guilliman, Regent of Terra, heads off to lead the Indomitus Crusade, he leaves behind a world still in turmoil, beset by cult activity. Stripped of its huge armies for the galactic offensive, recovery is precarious. The Custodians do what they can while keeping the Palace secure, and the Sisters of Silence rebuild their citadel on Luna. When the warship Phalanx returns, it seems that stability will at last be assured. However, as reconquest forces push out further into the slums, they come across signs that another mysterious foe is active.

The Traitor Host of Horus Lupercal tightens its iron grip on the Palace of Terra, and one by one the walls and bastions begin to crumple and collapse. Rogal Dorn, Praetorian of Terra, redoubles his efforts to keep the relentless enemy at bay, but his forces are vastly outnumbered and hopelessly outgunned. Dorn simply cannot defend everything. Any chance of survival now requires sacrifice, but what battles dare he lose so that others can be won? Is there one tactical stroke, one crucial combat, that could turn the tide forever and win the war outright? 

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?