When he came to, he found himself lying on his back a few metres away from the worm's smoking corpse. Astelan was kneeling beside him, twisting his legs back into their proper position. Dimly, he could feel the tingle of pain blockers blurring the edges of his mind.

'Hold still for a few moments more, until the bones knit,' the chapter master said as he orientated Zahariel's right calf and began inspecting the servo-motors around the knee-cap. 'Most of your actuators are shot, but you should still be able to move about.'

Zahariel nodded, focusing his thoughts on accelerating his healing faculties and taking stock of his armour. 'The queen?' he grunted.

'Dead,' Astelan confirmed. 'And the corpses went inert at the same moment. That was well done, brother. Luther would be proud.'

'What of Brother Gideon?' Zahariel asked.

'Comatose. His armour is keeping his vital signs stable enough that we should be able to get him back to Aldurukh.'

Satisfied, the Librarian lay his head back against the floor and spent the next few seconds testing the strength of his muscles and bones. Armour plates grated and crimson runes flashed insistently in the corners of his eyes as he carefully flexed first the left leg, then the right. He would be weak for a few minutes more as his body worked to repair the damage, but he was functional. Astelan offered his hand and he took it gladly as he rose carefully to his feet.

The worm queen's corpse was wreathed in tendrils of black smoke. Zahariel walked slowly over to the body of the monster and pulled his staff from the creature's forehead. The corpses it had controlled were sprawled about like puppets whose strings had been severed.

Feeble motion across the chamber caught Zahariel's eye. The queen's larval hosts were squirming and writhing away from the carnage, drawn by some primal instinct towards the illusory safety of the thermal core. Zahariel limped slowly after them, drawing once more on the psychic power of the warp. The energy came reluctantly, flowing through the dampener and coursing along the staff. It was nothing like the wild torrent of power he'd felt before, and he was relieved to note that the sense of dislocation was receding. The oily feeling of corruption still lingered, however, staining the very stone of the chamber and pooling in the blood-soaked runes carved into the floor.

Zahariel slew the larvae one by one, using the power of the staff to slay the host and snuff out the life of the monster within. The last of the abominations had reached the very base of the thermal core, its distorted face and thin arms stretching upwards as though pleading for aid from some nameless, atavistic power.

The Librarian glanced upwards at the core as the last of the larvae burned. He was close enough now to see the symbol that had been painted on the side of the thermal unit. The image was comprised of hundreds of tiny runes that stung his eyes when he tried to focus on them, but the picture they formed was easy enough to identify: an enormous serpent eating its own tail. An ouroboros, Zahariel thought.

Suddenly a voice crackled over his vox-unit, stirring him from his reverie. 'Angelus Six, this is Raider two-one. Angelus Six, come in.'

'This is Angelus Six,' Zahariel replied.

'It's good to hear your voice, brother,' the driver of the Land Raider said. 'We're picking up signals from beyond the perimeter again. Seraphim is calling urgently for a status update.'

Zahariel took one last look at the symbol on the thermal core, then turned back to his squad. What he had to say to Luther couldn't be shared over the vox net. 'Inform Seraphim that we've secured Objective Alpha and we're returning to base. I'll deliver my report to him personally. We'll be back on the surface in ten minutes.'

'Raider two-one copies, Angelus. Standing by.' Astelan stood at what had been the centre of the sorcerous spiral, well apart from the rest of his brothers. He had removed his helmet and was studying the runes cut into the stone. The chapter master looked up at Zahariel as the Librarian approached. His expression was haunted.

'What are we going to do about this?' he asked quietly.

Zahariel knew what Astelan meant. He reached up and pulled off his own helmet, grimacing at the strange mix of ozone and decay that permeated the air. 'I'll see to it,' he said. 'Gather the squad. We've got to get back and report to Luther at once.'

The chapter master nodded and turned away. Zahariel followed, keying his vox-unit.

'Broadsword Flight, this is Angelus Six.'

This time the reply came in loud and clear; the unnatural interference had subsided completely. 'Broadsword Flight copies,' said the leader of the Stormbird flight.

'Objective Alpha is compromised; repeat, Objective Alpha is compromised,' Zahariel replied. 'We are withdrawing in fifteen minutes. Execute Plan Damocles at that time.'

The Stormbird Leader answered without hesitation. 'Affirmative, Angelus Six. Plan Damocles in one-five minutes.'

Zahariel quickened his pace, passing Astelan and the rest of his squad. The Astartes fell in behind him, carrying both halves of Brother Gideon's limp form between them.

They had little time to spare. In fifteen minutes the Stormbirds from Broadsword Flight would level Sigma Five-One-Seven, destroying any evidence of what had transpired at the site.

The Dark Angels alone would know the truth. Otherwise, Caliban would surely die.

THIRTEEN

Secrets of the Past

For the next two and a half weeks, the Dark Angels and the people of Diamat worked day and night to prepare for the coming storm. Governor Kulik sent troops into the countryside to locate camps of refugees, conscripting all the healthy men and women he could find and putting them to work constructing new fortifications under the experienced eye of Jonson's veteran warriors. High above the forge, Jonson's warships lay at anchor - even the near-derelict Duchess Arbellatris, which had been towed back to Diamat by the light cruisers of the scout force - and were being worked over night and day by Magos Archoi's best tech-adepts. Flocks of cargo shuttles came and went daily, re-stocking the battle group's depleted stores of ammunition and heavy ordnance. Other craft ferried Governor Kulik and Magos Archoi to and from the Invincible Reason on a regular basis to confer with Primarch Jonson and refine their battle plan.

Nemiel was busier than he'd ever been. When he wasn't managing repair and resupply schedules or fielding requests from the captains of the battle group he was shuttling down to the planet's surface to help supervise the construction of defensive positions throughout the grey zone and implementing Jonson's organisational changes to the planetary defence force. He ate little and slept even less, devoting his full energy and attention to every task that was put in front of him. The officers of the fleet and members of Kulik's staff commented on his dedication and zeal, and held him up as an inspiration to the men under their command. Nemiel would wave away their praise. He was merely setting a proper example, he would say, as any Chaplain ought.

In truth, he consumed himself with work because it kept his growing doubts at bay. He couldn't help but think about his conversation with Jonson, and his evasive replies. The primarch wasn't a brigand, Nemiel knew; he hadn't come all the way to Diamat to sack its forges, as Horus's men had done. Yet he couldn't shake the notion that Jonson wasn't telling him the entire truth, and that went against everything Nemiel thought that the Legion stood for.