The Saroshi had been a highly cultured people who hid a terrible canker at the heart of their civilization. Sometime during the nightmare known as the Age of Strife they had sealed a pact with a horrific entity in exchange for their survival. When the Dark Angels had assumed the task of formalising Saroshi compliance, the Saroshi leaders had attempted to assassinate their primarch by smuggling an atomic warhead onto the flagship. Had the bomb not been discovered and dealt with by Luther and Zahariel, the Legion would have been dealt a catastrophic blow or so the story went.

Luther never brought up the incident during the length of the voyage back to Caliban, but the question hung in the air between them. Had Jonson suspected the truth? Was that why Luther had been sent away, and was Zahariel being punished by virtue of his association to the event?

There was no way to know.

The space port was one of five within a two-hundred-square-kilometre perimeter around the Legion fortress of Aldurukh. Zahariel could remember a time when the land had been covered in dense forest that teemed with deadly plant and animal life. Caliban was considered by Imperial planetologists to be a ''death world'' - a planet that wasn't merely dangerous but actively inimical to human life. Every day had been a struggle for survival, and life was both brutal and often very short. It was only through the courage and sacrifice of the planet's knightly orders that humanity survived at all.

Lion El'Jonson had united all the knightly orders under his leadership and had led a successful campaign to eradicate the deadliest of Caliban's monsters, but the final blow had come in the form of the Imperium. The Emperor's servants had descended on the planet with enormous machines that cleared dozens of kilometres of forest a day and left flat, lifeless earth in their wake. Mines, refineries and manufactorums had followed, ready to transform the planet's abundant resources into vital war materiel for the Emperor's Crusade. Cities were built to supply the sprawling industrial sites, growing upwards and outwards with each passing year as villages and towns were emptied and their citizens relocated to better serve the Imperium.

In the past, more than two dozen villages and settlements had supported the fortress of Aldurukh, providing everything from food to clothing, metal ore and medicines so that the knights were free to hone their skills and defend the land from the beasts. All of them were gone now; the land surrounding the fortress had been levelled and transformed into a vast military and logistical complex. Zahariel would have been hard-put to recall where any of the villages had once stood. Now, in addition to the space ports, there were training centres, barracks, arsenals, storehouses and maintenance yards stretching as far as the eye could see, all dedicated to supplying the Legion with the men and equipment it needed to fulfil its role in the Great Crusade.

Even at such a late hour, the cadre went almost unnoticed in the bustling activity surrounding the fortress. Cargo lifters and shuttles came and went between the space ports and the harbours in high orbit, ferrying supplies and personnel destined for the front lines. The Dark Angels passed long convoys of ordnance haulers and supply trucks on their way to and from the landing fields. Platoons of armoured vehicles roared past, heading for the marshalling yards south of the fortress or to the training grounds for the Legion's auxiliary Imperial Army units. Once, a regiment of new Army recruits stopped in its tracks and shuffled quickly off the road to let the Astartes pass. The young men and women in their crisp new battle-dress stared open-mouthed at the marching giants and the golden-armoured figure who led them.

They marched through the rain and the wind for ten kilometres, passing through curtain walls made from permacrete and studded with defensive shield projectors and automated weapon emplacements. The closer they drew to Aldurukh, the denser and higher the structures grew, until finally the Astartes found themselves marching down man-made canyons lit solely by globes of artificial light.

Yet Aldurukh rose above all else, a bastion of strength and tradition surrounded by a sea of constant change. Its granite flanks had been scraped bare by Imperial construction machines; even now, titanic excavators scaled its sheer sides, carving out ledges and boring tunnels deep into the rock as the fortress continued to expand into the heart of the mountain itself. Zahariel had heard of plans to one day create a series of gates at the foot of the mountain that would provide access to the fortress's subterranean levels as well as lifts that would carry passengers up into the centre of the fortress within seconds. For all its efficiency, the notion seemed vaguely offensive to him; the path up the Errant's Road to the castle gates had been trod by the knights of the Order for centuries, and had taken on great spiritual significance in their legends and lore. His brothers could ride the lifts if they preferred; he intended to walk the path built by his elders for as long as he was able.

To his relief, the fortress hadn't yet changed so much in the years he'd been away. At the base of the mountain, rising incongruously to either side of a narrow, paved lane that passed between two towering barracks facilities, stood the ancient, weathered menhirs that marked the foot of the old road. The old stones depicted the beginning and ending stages of a knight's journey: the left menhir was carved in the likeness of a proud knight striding forth into the world, pistol and chainsword in hand; the one on the right showed a battered and weary warrior, his armour splintered and his weapons broken, kneeling wearily but with head held high as he contemplated his return home. Zahariel smiled to see Luther brush his fingertips lightly against the right-hand menhir as he passed by, a tradition that reached back to the earliest days of their brotherhood. He repeated the gesture, feeling the smooth stone beneath his fingertips and thinking of the generations of his forbears who had done the same, stretching back for millennia.

The storm broke as they trod the narrow, winding road, though the wind still tangled their surplices and tugged at their hoods as the clouds paled with the first light of dawn. The climb, though long, passed quicker than Zahariel expected. After what seemed like only a couple of hours he found himself upon a broad, paved square that in times past had been a forested clearing, where aspirants to the Order once spent a long and harrowing night before the castle gates.

Now those gates were thrown wide open as the Dark Angels approached, and Zahariel saw with surprise that the courtyard beyond was filled with ranks of young recruits, arrayed to create a processional that led to the feet of the castle's outer citadel. The recruits had been assembled in haste; many of them stared at the new arrivals with an equal mix of curiosity and surprise.

Luther led his warriors down the length of the processional as though he'd expected the impromptu assembly all along. At the far end of the long line of recruits waited two figures: one wasted and bent with age, the other clad in dark armour and a surplice hemmed with gold. He stopped at a respectful distance from the two, and behind him the cadre of Astartes came to a thundering halt.

As if on cue, the assembled recruits sank to one knee and bowed their heads to the golden knight. A trumpet pealed from the castle gatehouse, the traditional signal for a knight home from a long and dangerous quest. Master Remiel, of late the Castellan of Aldurukh, knelt before Luther as well. Behind Remiel, Lord Cypher inclined his head respectfully to the Legion's second-in-command, though Zahariel could not help but notice a faint glitter of amusement in the warrior's eyes.