Loken forced himself to look at the book, feeling his heart grow heavy with each word he read from its yellowed pages.

I am Horus, forged of the Oldest Gods,

I am he who gave way to Khaos

I am that great destroyer of all.

I am he who did what seemed good to him,

And set doom in the palace of my will.

Mine is the fate of those who move along

This serpentine path.

'I'm no student of poetry,' snapped Loken. 'What does it mean?'

'It's a prophecy,' said Sindermann hesitantly. 'It speaks of a time when the world returns to its original chaos and the hidden aspects of the supreme gods become the new serpent.'

'I don't have time for metaphors, Kyril,' warned Loken.

'At its most basic level,' said Sindermann, 'it speaks about the death of the universe.'

Sejanus found him on the steps of a vaulted basilica, its wide doorway flanked by tall skeletons wrapped in funeral robes and holding flaming censers out before them. Though darkness had fallen, the streets of the city still thronged with worshippers, each carrying a lit taper or lantern to light the way.

Horus looked up as Sejanus approached, thinking that the processions of light through the city would have seemed beautiful at any other time. The pageantry and pomp of the palanquins and altars being carried along the streets would previously have irritated him, were the procession in his honour, but now he craved them.

'Have you seen all you need to see?' asked Sejanus, sitting beside him on the steps.

'Yes,' replied Horus. 'I wish to leave this place.'

'We can leave whenever you want, just say the word,' said Sejanus. 'There is more you need to see anyway, and our time is not infinite. Your body is dying and you must make your choice before you are beyond the help of even the powers that dwell in the warp.'

'This choice,' asked Horus, 'Does it involve what I think it does?'

'Only you can decide that,' said Sejanus as the doors to the basilica opened behind them.

Horus looked over his shoulder, seeing a familiar oblong of light where he would have expected to see a darkened vestibule.

'Very well,' he said, standing and turning towards the light. 'So where are we going now?'

'To the beginning,' answered Sejanus.

Stepping through the light, Horus found himself standing in what appeared to be a colossal laboratory, its cavernous walls formed of white steel and silver panels. The air tasted sterile, and Horus could tell that the temperature of the air was close to freezing. Hundreds of figures encased in fully enclosed white oversuits with reflective gold visors filled the laboratory, working at row upon row of humming gold machines that sat atop long, steel benches.

Hissing puffs of vapour feathered the air above each worker's head, and long tubes coiled around the. legs and arms of the white suits before hooking into cumbersome looking backpacks. Though no words were spoken, a sense of the implementation of grand designs was palpable. Horus wandered through the facility, its inhabitants ignoring him as completely as those of the shrine world had. Instinctively, he knew that he and Sejanus were far beneath the surface of whatever world they had travelled to.

'Where are we now?' he asked. 'When are we?'

'Terra,' said Sejanus, 'at the dawn of a new age.'

'What does that mean?'

In answer to his question, Sejanus pointed to the far wall of the laboratory where a shimmering energy field protected a huge silver steel door. The sign of the aquila was etched into the metal, along with strange, mystical looking symbols that were out of place in a laboratory dedicated to the pursuit of science. Just looking at the door made Horus uneasy, as though whatever lay beyond was somehow a threat to him.

'What lies beyond that door?' asked Horus, backing away from the silver portal.

'Truths you will not want to see,' replied Sejanus, 'and answers you will not want to hear.'

Horus felt a strange, previously unknown sensation stir in his belly and fought to quell it as he realised that, despite all the cunning wrought into his creation, the sensation was fear. Nothing good could live behind that door. Its secrets were best forgotten, and whatever knowledge lay beyond should be left hidden.

'I don't want to know,' said Horus, turning from the door. 'It's too much.'

'You fear to seek answers?' asked Sejanus angrily. 'This is not the Horus I followed into battle for two centuries. The Horus I knew would not shirk from uncomfortable truths.'

'Maybe not, but I still don't want to see it,' said Horus.

'I'm afraid you don't have a choice, my friend,' said Sejanus. Horus looked up to see that he now stood in front of the door, wisps of freezing air gusting from its base as it slowly raised and the energy field dissipated. Flashing yellow lights swirled to either side of the door, but no one in the laboratory paid any attention as the door slid up into the panelled wall.

Dark knowledge lay beyond, of that Horus was certain, just as certainly as he knew that he could not ignore the temptation of discovering the secrets it kept hidden. He had to know what it concealed. Sejanus was right; it wasn't in his nature to back away from anything, no matter what it was. He had faced all the terrors the galaxy had to show him and had not flinched. This would be no different. Very well,' he said. 'Show me.'

Sejanus smiled and slapped his palm against Horus's shoulder guard, saying, 'I knew we could count on you, my friend. This will not be easy for you, but know that we would not show you this unless it was necessary.'

'Do what you must,' said Horus, shaking off the hand. For the briefest instant, Sejanus's reflection blurred like a shimmering mask in the gleaming metal of the door, and Horus fancied he saw a reptilian grin on his friend's face. 'Let's just get it done.'

They walked through the icy mist together, passing along a wide, steel-walled corridor that led to an identical door, which also slid into the ceiling as they approached.

The chamber beyond was perhaps half the size of the laboratory. Its walls were pristine and sterile, and it was empty of technicians and scientists. The floor was smooth concrete and the temperature cool rather than cold.

A raised central walkway ran the length of the chamber with ten large cylindrical tanks the size of boarding torpedoes lying flat to either side of it, long serial numbers stencilled on their flanks. Steam gusted from the top of each tank like breath. Beneath the serial numbers were the same mystical symbols he had seen on the door leading to this place.

Each tank was connected to a collection of strange machines, whose purpose Horus could not even begin to guess at. Their technologies were unlike anything he had ever seen, their construction beyond even his incredible intellect.

He climbed the metal stairs that led to the walkway, hearing strange sounds like fists on metal as he reached the top. Now atop the walkway, he could see that each tank had a wide hatchway at its end, with a wheel handle in its centre and a thick sheet of armoured glass above it.

Brilliant light flickered behind each block of glass and the very air thrummed with potential. Something about all this seemed dreadfully familiar to Horus and he felt an irresistible urge to know what lay within the tanks while simultaneously dreading what he might see.

'What are these?' he asked as he heard Sejanus climbing up behind him.

'I'm not surprised you don't remember. It's been over two hundred years.'

Horus leaned forward and wiped his gauntlet across the fogged glass of the first tank's hatch. He squinted against the brightness, straining to see what lay within. The light was blinding, a motion blurred shape within twisting like dark smoke in the wind.