For a thousand years, the Sabbat Worlds have been lost to the Imperium, claimed by the dread powers of Chaos. Now, a mighty crusade seeks to return the sector to Imperial rule. And at the forefront of that crusade are Colonel-Commissar Ibram Gaunt and the Tanith First and Only - better known as Gaunt’s Ghosts. Trapped in the grinding trench warfare of Fortis Binary, the Ghosts find themselves drawn into a conspiracy to assassinate the crusade’s leader, Warmaster Macaroth.

The eldar are an ancient race whose mode of war blends spirituality with a unique mastery of technology. In times of need, their entire race will rouse to war, led by terrifying, almost mythological figures - the phoenix lords, immortal beings that embody the warrior nature of the eldar. When a burgeoning ork empire starts to pose a threat to the eldar peoples, Jain Zar travels to the craftworld Ulthwé to warn them of the danger.

The Aeronautica Imperialis are the masters of the skies in the 41st millennium, waging wars of breakneck aerial combat where only skill stands between victory and death. Flight Commander Lucille von Shard is an ace, a living exemplar of what it means to fly in the name of the Emperor… or so Propagandist Kile Simlex is told. Braving the foetid waters of Bacchus and its rampaging greenskin hordes, Simlex is tasked with producing a cinema-pict portraying Shard as an Imperial hero. Shortly after his arrival planetside, however, he discovers the war effort is in shambles.

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.

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.

When his body is hideously damaged in an enemy attack, it looks as though Inquisitor Gideon Ravenor's promising career would be abruptly brought short. Now, encased in a life support sytem that keeps him alive but forever cuts him off from the physical world, Ravenor utilises his formidable mental powers to continue his investigations. Along with his retinue of warriors and assassins, Gideon Ravenor fights to protect an Imperium he can no longer see, hear or feel.

Under almost constant besiegement by the hosts pouring from the Eye of Terror, Cadia acts as a bulwark against tyranny and death. Its fortresses and armies have held back the hordes of Chaos for centuries, but that grim defiance is about to reach its end. As Abaddon's Thirteenth Black Crusade batters Cadia's defences, and armies of the Imperium flock to reinforce this crucial world, a terrible ritual long in the making comes to fruition and the delicate balance of this brutal war shifts.

The Battle Titans of the Adeptus Titanicus are towering war engines, striding to war as holy effigies of the Omnissiah. Greatest of all are the mighty Warlord Titans, their weapons bringing righteous death to alien and heretic alike. Still reeling from a near disastrous battle against tyranids, the Pallidus Morr demi-legio is assigned to a new warzone, a nearby forge world which has fallen under the sway of Chaos.

In the age of the Dark Imperium, Primarch Guilliman’s Primaris Ultramarines are a shining beacon in the darkness of war. On the Imperial Hive World of Ikara IX, Chaplain Kastor and Apothecary Polixis, brothers in blood as well as in battle, stand firm against the endless Greenskin horde. But a threat is looming. An invasion like no other assaults the broken city of Shebat, as the crazed warlord Urgork arrives to lay waste to the Imperial forces and capture a Primaris Marine for his own twisted ends.

A great darkness has befallen the galaxy, and the armies of Chaos are rampant. To survive, humanity must retaliate and take back what they have lost. By the will of the reborn primarch, Roboute Guilliman, is the Indomitus Crusade launched - a military undertaking that eclipses all others in known history. From the Throneworld of Terra does the Avenging Son hurl his fleets, their mission the very salvation of mankind.