‘So I spent – what, twenty-four years? – on Per Ardua, planet of Proxima Centauri. With Mardina Jones, and our baby Beth, and you, ColU. Struggling to stay alive. We found others, other “colonists” stranded as we had been, and we fought our way to the Hub of the world, the substellar. There we found—’

‘A Hatch.’

‘A step through, just that, and we were back on planet Mercury, across four light years. So, everything changed yet again, for humanity, for me. I had taken Mardina and Beth home, and that’s where they stayed …’

‘But you couldn’t stay with them.’

‘For me, it was go back to Ardua, or face jail. So, back to Ardua it was, with Stef Kalinski at my side. Who has her own issues with all of this, by the way.’

‘Are you tiring, Yuri Eden?’

‘Don’t fuss, ColU. I hate it when you fuss. Back to the story. So, on Ardua, the UN started to clamp down, just like it had in the solar system, because war was brewing up. A war to be fought with kernel-powered ships, over the lodes of kernels on Mercury …’

‘Yuri Eden?’

‘Still here, ColU.’

‘Do you remember how we drove to the antistellar point? The darkest, coldest place on Per Ardua, in the deepest shadow of Proxima. Where we found, among other mysteries, another Hatch.’

‘Yes, the Hatch. And we stepped through, Stef and I, and you. We found ourselves under the light of another star. And there was a man, in a cloak and a helmet, striding towards us …’

Quid estis?

‘Yes. Do you remember, Yuri Eden?’

Quid agitis in hac provincia? …

CHAPTER 2

AD 2222; AUC 2975

The intruders at the Hatch emplacement were first spotted by sharp-eyed Arab navigators aboard the Malleus Jesu. In their quiet chambers aboard the interstellar craft circling high above this world, the Arabs, doubling as observers and map-makers here at the destination, routinely scrutinised the area around the Hatch through their farwatchers. The newly minted Hatch was the key objective of the mission, after all, and deserved surveillance and protection.

And now Centurion Quintus Fabius himself was in the air, on the way to investigate.

The leather sac of the aerial cetus creaked and snapped as the great craft shifted in the light wind. Quintus was standing alongside the command position, a bank of levers worked by a remex, one of the junior crew who reported to Movena, the trierarchus, the commander of the ship itself. Like Movena, this remex was a Brikanti, and just as arrogant and sullen as Movena herself and all her kind. And yet you couldn’t argue about his competence. As he stroked his levers great paddles shifted in the air around the flank of the cetus, and the craft moved sweetly in response, heading towards the Hatch, which stood open on the scarred plain that Quintus’s engineers had made when they had unleashed the hot breath of the kernels on this world, and created this wonder.

The bridge of the cetus was a clutter of controls and instruments, and scuffed wooden tables on which lay heaped charts and itineraries, mappings of this world hand-drawn since the expedition’s arrival three years ago. The air was redolent with the characteristic scent of the Brikanti, the folk of the uncivilised north, with the mead they drank and the treated hog-leather they wore, and the tang of the Valhallan tobacco they liked to chew as they worked.

But this mundanity terminated at the window, before which an alien world unfolded before Quintus’s eyes. Even after three years, even after he had walked so much of it – and even after he had changed its face significantly by building roads and camps and the permanent colony, and of course creating the Hatch – still Quintus found this world astounding.

The Hatch itself had been set on a scrap of higher land, overlooking a plain on which native vegetation sprawled, a low scrub of purple and white studded with odd orange cones. The Greek philosophers aboard assured Quintus that the cones were communities of creatures mostly too small to see – cities of the invisible, each mound a Rome of the germs. Further away the land rose up, ascending towards lofty mountains before which foothills stood in attendance. And those mountains and hills, each a massive plug of volcanic rock, had been shaped, with terraces and walls and mighty crenellations that cast sharp shadows in the unchanging mother-of-pearl light of the principal sun Romulus. They were mountains turned into fortresses by beings who had once lived here, and remade their world, and vanished – blown themselves to bits, no doubt, Quintus had heard his gloomier legionaries conclude in the camps. And yet those mountain-sculptors evidently shared something with the rudest legionary from the poorest province of the Empire: they had built Hatches.

Well, Quintus had brought his ship here, and the engineers and the legionaries and the slaves had built their own Hatch, and their names would be remembered for it, the ancient number of the legion of which this century was a part inscribed at the foot of the stone Cross of Jesu that was the only human monument permitted to accompany a Hatch. This was forever Quintus’s Hatch. And this world, the fourth of the family that surrounded this stellar twin, Romulus, would, once the permanent colonia was formally dedicated by the vicarius, become the latest province of a Roman Empire that had now reached to the stars themselves.

This was what he had achieved, he, Quintus Fabius; this was what he had bought at what would be the cost of thirteen years of his own life away from home, and, thanks to the mysteries of near-lightspeed travel, a sundering by many more years than that from the family and friends he had left behind. It was a price he paid gladly; to command such a vessel as the Malleus Jesu, on such a mission as this, to build a Hatch, was the pinnacle of his career so far – and likely not to be surpassed, he reminded himself with a twinge of resentment, as it was rare for officers from the provinces to rise much further in the imperial army unless you were wily enough for intrigue and assassination. Yet the Hatch was not for Fabius, or his crew, or any human; the Hatch was a thing in itself, its own purpose as ineffable as that of a temple to a forgotten god.

And now, as he peered down from a washed-out sky, the perfection of the Hatch and its setting was ruined by the intruders. As the cetus made its ponderous way towards the Hatch position, Quintus felt his temper boil up, and he clenched and unclenched one massive fist, feeling the muscles in his arm work.

‘Two of them,’ said Gnaeus Junius. Gnaeus was Quintus’s optio, his second in command. Gnaeus was peering down at the Hatch location through a finely wrought Greek farwatcher, leather and glass in a wooden tube.

‘Give me that.’ Quintus grabbed the instrument from Gnaeus’s hands and held it up to his eye. As usual, at first, he saw only darkness.

‘You need not squint so much, sir.’

‘I’m angry. When I’m angry, I squint.’

‘Yes, sir. You also grind your teeth.’

‘No, I don’t.’

‘No, sir.’

Slim, dark, elegant, his tunic always spotless, Gnaeus Junius was an equestrian, a member of one of Rome’s oldest aristocratic pedigrees. Gnaeus, though so young, was likeable, flawlessly competent, and had displayed none of the arrogance or sense of entitlement redolent of so many of his class. Quintus had found him utterly dependable. None of which saved Quintus from a sour resentment that this boy was destined to rise far higher in the army and beyond it than Quintus himself ever could – that the only way Quintus could avoid having to report to this elegant boy some day would be retirement.

Now Gnaeus reminded him calmly of the issue in question. ‘So, about the intruders, sir. Two of them.’