Past the old summerhouse was one of the habitat's prettiest lakes, where crested devilfish swam between trailing branches of silver-barked fin-gertrees.

Phrantis wandered across the quaint little bridge that spanned the lake and watched a captive flock of jewelbirds wheeling beneath the clear blue dome.

The jewelbirds scattered as if in fright. Then the sounds reached Phrantis - reverberating booms like some huge hammer striking the surface of the dome. Ugly black cracks suddenly ran across a section of the dome and, with a sound like thunder, the section shattered.

Huge sheets of glass like giant knife blades fell, embedding themselves in the ground within sight of the lake. There was a growl of rushing wind as the heat within the dome rushed out into the cooler atmosphere beyond. A massive tear had been gouged out of the dome and Phrantis saw with horror the roiling grey-white clouds of the planetoid outside. The trees shook and -the water rippled. Phrantis's jewelled robes ruffled in the wind and he felt a sudden cold wash over him.

A tiny black shape dropped from the storm clouds towards the tear in the dome. As it plummeted closer Phrantis could see that it was like a bulb of metal, ringed with restraints, segmented like the unopened bud of an ugly grey flower. Bright flares ripped from its underside to decelerate it but when it landed, maybe three hundred metres from Phrantis, it still hit the manicured lawn in a fountain of earth. Two more followed, then a fourth, and Phrantis realised the last one was heading for the lake.

He turned to run, but his old frame had barely lurched a few steps when something massive thudded into the lake, drenching him in a wave of spray. He turned to see the metal seed pod bursting open and the purple-armoured soldiers inside - ten of them - snapped off their restraints and waded out into the water of the lake! The lake was quite deep but their heads still showed above the water, indicating they must be a good metre taller than Phrantis himself. Phrantis knew of the Adeptus Astartes - he had occasionally come across those superhuman warriors in his career - and he had no doubt that Space Marines were invading House Jenassis.

The House had been loyal. It had served the Imperium with all its energy, asking only gratitude in return. Why would Space Marines be attacking a House that had helped the Imperium maintain its grip on the galaxy?

The Marines were already clambering up the bank, each with a pistol in one hand and an out-sized chainsword in the other. Each wore the emblem of a chalice on his shoulder pad. One had some kind of attachment for a hand - Phrantis realised with a start that it was not a bionic but the grotesquely warped hand itself, with long muscular multi-jointed fingers gripping the haft of a power axe. The helmetless Marine wielding it was a grizzled veteran, face battered and scarred, and he had spotted Phrantis.

Phrantis didn't run. He was old, and they would easily outpace him. Either that, or his long and distinguished life would end with a bolter shell in the back. The closest Marine clambered up the bank, covered the distance in a few long strides, and dragged Phrantis to the ground by the scruff of his neck.

The sergeant with the mutant hand ran over. The power field around the blade of his axe was activated and droplets of water were hissing on the metal.

'You. What is your name?'

'Patriarch Phrantis Jenassis of House Jenassis.' Phrantis was amazed he had been able to answer.

'A Navigator?'

Phrantis nodded.

'Bind his hands.’ said the sergeant to the Marine holding Phrantis down. 'Don't let him take his turban off. His warp eye'll kill you.'

Phrantis's hands were pulled behind his back and a plastic restraint tied around his wrists.

'What do you want?' gasped Phrantis. 'We are loyal here. We have been loyal since the days the Emperor still walked amongst us! Our warrant of binding was signed by his hand! We are loyal!'

The sergeant grinned, showing broken teeth. We're not.’ he said.

Phrantis was hauled to his feet. Not loyal? Phrantis had heard dark tales of Space Marines who fell from grace and joined the great enemy, the powers of Chaos that could not be named by righteous lips. Chaos Marines, all the pride and vigour of Space Marines turned to cruelty, bloodlust and desecration.

A warzone, where the Chaos Warlord Teturact was carving out an empire, was only a couple of subsec-tors from House Jenassis. Phrantis had been assured that the warfleets massing on the border of the war-zone protected House Jenassis from Chaos raiders, but perhaps those raiders had found a way through. Had these Marines come from the Teturact's hordes? What could they want with House Jenassis? Navigators for their fleets? Slaves? Or just the despoiling of somewhere beautiful?

Phrantis saw other purple-armoured giants moving away from the other pods that had fallen, taking up firing positions amongst the trees. With the breach in the dome the sky was darker and a chill wind was blowing down from above. Beautiful House Jenassis was already imperfect.

'Commander?' the sergeant was saying into his communicator. 'We've taken the patriarch. I'm heading to your position now. No other contacts. Over.’ There was a pause as someone made a reply Phrantis couldn't hear. 'I see you. Graevus out.’

Phrantis followed Sergeant Graevus's gaze, and saw a nightmare.

COMMANDER SARPEDON, Chief Librarian and Chapter Master of the Soul Drinkers, was a half arachnid mutant renegade. His eight legs - seven chitinous limbs and one bionic - skittered rapidly as he moved with Squad Hastis across the rolling lawns towards where Squad Graevus was advancing with their prisoner. The boots of Hastis's Marines churned up the manicured grounds.

Sarpedon met up with Graevus in the shadow of a spreading alien tree with scarlet leaves that cast a dim shadow beneath the darkening sky. Graevus, like most of the Chapter, was a mutant - his hand had deformed to give him greater strength and reach with the power axe he carried. Squads Hastis and Krydel were setting up a perimeter in case the planet's Arbites or Navigator House retainers arrived quickly. Techmarine Solun, the Marine whose machine-skills would make the difference between success and failure here on Kytellion Prime, was with Squad Krydel, the mem-plates covering his armour glinting black.

Phrantis Jenassis was a grey-haired, thin-faced slip of a man in ruby-red robes embroidered with gold and gemstones. A turban wrapped around his head concealed the third eye, the warp eye, in the centre of his forehead. It could look out on the warp itself but also, they said, kill a man with a glance.

'He's unhurt,' said Graevus. 'We found him alone.'

'He will not be alone for long.’ said Sarpedon. He turned to the shivering patriarch. "Where is the Galactarium?'

Phrantis looked up blankly for a moment. 'I will not yield, Chaos filth.’ he stuttered.

Sarpedon reached down and grabbed Phrantis by the chin. 'Do not waste our time, old man. We do the work of the Emperor. Where is the Galactarium?'

'The... the Arbites will be here, we have a precinct dedicated to our protection...'

Sarpedon cursed the fragmented intelligence he had been able to muster on House Jenassis. The Soul Drinkers knew the Galactarium was here - one of the wonders of the Imperium, by all accounts -but there had been no map of the house environs to plan the assault properly. 'We will kill them all if we have to.’ said Sarpedon, knowing they would if it came down to it. 'That does not have to happen. All we want is access to the Galactarium, then we will go. House Jenassis can run back to the Imperium in safety if you just give us what we want.’

Phrantis Jenassis closed his eyes and whimpered, trying to shut out the cold, dangerous place his home had suddenly become.