It is the 32nd millennium, and the Imperium is at peace. The Traitor Legions of Chaos are but a distant memory, and the many alien races that have long plagued mankind are held in check by the Space Marines. When a mission to exterminate one such xenos breed on the world of Ardamantua draws in more of their forces, the Imperial Fists abandon the walls of Terra for the first time in more than a thousand years.

As ork ships lay waste to world after world, heading inexorably towards Terra, Imperial citizens despair. The High Lords become desperate to prove that victory is possible, no matter the cost. A massive navy fleet is assembled - their mission to make a definitive strike against the orks at Port Sanctus, an area of enemy-held space. But when the Imperial armada arrives, they find themselves outclassed and outmanoeuvred. Can human courage and faith possibly prevail against such terrible odds?

Despite the Imperium's best attempts to forestall the ork plague that is wreaking havoc in human space, an ork attack moon now hangs over Terra. As its malevolent presence gazes down at the Imperial Palace, terrified citizens run riot in the streets. In a last-ditch attempt to destroy the attack moon, a proletarian crusade is launched. Thousands of ships large and small head to the moon carrying billions of citizens, all eager to take the fight to the enemy.

The Imperium's situation has never been more grim - an ork attack moon hangs over Terra, and ork armadas ravage human space. To make matters even worse, eldar strike at the heart of the Imperial Palace, forcing humanity's defenders to fight on two fronts at once. Though it seems nothing can stop the orks - neither brute force, science, nor faith - an unlikely alliance in the furthest reaches of space uncovers the first clue how to defeat the greenskins. The Adeptus Astartes now face an almost impossible task....

Paralysed by the continued ork invasion of Imperial space, the rulers of Terra continue to fight among themselves. Finally losing patience with the High Council, Koorland - the last surviving Imperial Fist - ousts the Lord Commander and seizes control. Elsewhere, the Fists Exemplar are forced by circumstance to fight alongside the Iron Warriors. Where will such an alliance lead - can a Traitor Legion ever be trusted?

The Imperium has been brought to the edge of extinction by an ork invasion of unprecedented scale and depth. Piecemeal strikes against the invaders prove ineffective - for every ork fleet destroyed, five more appear. The only solution is to find and kill the orks' warlord - the Great Beast. Surely if its leader is killed, the greenskins' empire will fall apart in agony of infighting and confusion.

As the ork menace ravages the galaxy, the Imperium faces its darkest hour. Its fleets are in ruins, its armies devastated - amongst them the noble Imperial Fists - and even a primarch of myth has fallen against the Beast. As brute force fails, Koorland resorts to increasingly desperate tactics against the greenskins. A final hope lies in deploying the controversial Deathwatch and the Sisters of Silence in a deft strike at the heart of the ork empire.

The Imperium's attempts to defeat the ork menace seem doomed to failure; it is only a matter of time before the greenskins triumph, and mankind is wiped from the galaxy. Yet there is some cause for hope - the psychic weakness of the orks has been found, and a few Sisters of Silence survive. Supported by the full might and technology of the Adeptus Mechanicus, the Space Marines head to the orks' home world one final time. This time there will be no retreat, no surrender. They must succeed...or die in the attempt.

Across the length and breadth of the galaxy, humankind celebrates its salvation and relishes the prospect of a return to peace. But the war against the orks has driven the political bedrock of the Imperium, exposing its rotten core. One man, one powerful man, decides he has the solution and launches a campaign of destruction so terrible that thousands of years later his actions will still be viewed with horror.

Of the billions of greenskins who swarm the galaxy, the name of one strikes fear into the hearts of human and xenos alike—Ghazghkull Mag Uruk Thraka. The Warlord of Warlords. The Beast of Armageddon. The Prophet of the Waaagh! With his tusks, fists and power claw, he does the holy work of Gork and Mork—and soon all worlds will burn in his bootprints. Mystery shrouds the origins of such a beast. Rumours abound that the mighty warlord was once just like any other ork—but if that is the case, how did he rise from a lowly lad to the biggest of bosses? 

The Horus Heresy is over. The traitor Legions have scattered, fleeing the wrath of a vengeful Imperium. The World Eaters are leaderless, their primarch missing and their greatest hero, Khârn, locked in a coma. The surviving Legionaries have turned upon themselves, their Butcher's Nails driving them to ever-greater acts of berserk savagery. Poised on the brink of destruction, the Legion needs direction. 

In the ruined border town of Vincula, the newly formed Tanith First and Only and their commander, Colonel-Commissar Ibram Gaunt, are assigned to enforce a permanent peace. However, this thankless police action will prove as dangerous as any frontline—something is stalking the Ghosts through the streets, and soon the Tanith First will learn dark secrets about themselves that will echo through their history.

The Death Korps of Krieg are deployed to a soul-crushing siege in the Octarius War Zone. They’re the right regiment for the job, though victory might come at a price that some might balk to pay.

Huron Blackheart is the lord of the Red Corsairs, master of the lawless Maelstrom and its piratical denizens—but oathbreakers and renegades can seldom rely on the loyalty of their followers. With the galaxy thrown into turmoil by the return of Roboute Guilliman, the former Tyrant of Badab faces a renewed Imperium and fresh challengers emerging within his own ranks. Huron must call on every trick he knows to stay in control—and alive. 

The Indomitus Crusade continues its war across the stars. The primarch Roboute Guilliman has finally broken through the orkish threat bedevilling the sectors near Fenris, and makes ready to push on his bid to stabilise the Imperium Sanctus—but old and bitter foes stand in his way. Kor Phaeron, the Dark Cardinal, threatens the previously stable core of the Segmentum Solar. Waves of rebellion instigated by his infiltrating priests suggest an imminent, large-scale invasion by the Word Bearers Legion.