Stef pressed, ‘And then the second door, to the next chamber?’

‘I have explored the second chamber,’ Earthshine said. ‘Or at least I have sent secondary units in there. I believe I know what lies beyond the next door – and on the far side of this Hatch itself. But I have yet to open that final door. I have constructed a probe. You might be interested in the details, Stef. A sphere, of material of very high heat capacity. I hope it will last a measurable time, even as much as a nanosecond.’

Stef tried to imagine this. ‘What are you saying, Earthshine? What lies beyond that door?’

Earthshine whispered, ‘The ColU knows – or suspects.’

‘The boundary,’ said ColU. ‘The edge of the multiverse. The death of the future. Yes. That is what they would bring you here to show you. So that you could understand …’

‘There need be no spatial deviation, you see,’ said Earthshine. ‘You need not travel across space to reach it. And you need journey only a short distance into the future. After all, the event will occur everywhere, simultaneously. On every world.’

The ColU said, ‘We must compare our estimates of the time remaining.’

The humans absorbed this terrible conversation in silence.

Stef said at last, ‘And that’s what you’ve told Ari and Inguill they will walk into, if—’

‘If they are in the second chamber when the Hatch opens, yes. But they won’t listen, Stef. They don’t believe me. They believe that the Hatch will fulfil their dreams of power and wealth.’

Titus shook his head. ‘Then what are we to do?’

Stef sighed. ‘I suggest we try to get Ari and Inguill out of there. After all you are family, Beth, Mardina. You might get through where Earthshine couldn’t. And then—’

‘And then,’ the ColU said, ‘we must consider how best to use the time remaining to us.’

Mardina rested her hand on her belly, dropped her head, and reached blindly for Chu.

CHAPTER 71

The group spent two full days trying to coax Ari and Inguill out of the pit. Beth tried the hardest, tried to get through to the man she’d almost married. Even Mardina reluctantly consented to speak to Ari, about the baby she was carrying, his grandchild.

Neither basic human appeals, nor Earthshine’s cold logic about what must lie beyond the Hatch door, made any difference. Ari did seem anguished about the fate of the baby. But nothing would change his mind, nor Inguill’s, who babbled about the power of Inti, the Inca sun god. They were both convinced of only one thing: that Earthshine was trying to keep them from – well, from glory, Stef supposed.

Titus remarked, ‘No mortal should seek the power of a god. It would burn him in a flash.’

The ColU seemed to agree. ‘But who are we to stop them, Titus Valerius?’

At last, they gave up. Earthshine agreed to open up the Hatch for them.

The group gathered at the lip of the pit to see the outcome.

In response to Earthshine’s invisible signal, the door to the Hatch’s middle chamber swung back at last. In that chamber Stef could see the ‘probe’ Earthshine had mentioned, a fat ceramic sphere sitting on the chamber floor.

Ari and Inguill stepped through, moving gingerly, helping each other. At each step of the way Earthshine paused to allow them to reconsider, to pull back.

But at last they pulled the door closed behind them, without a backward glance, and they were gone.

‘I gave them a control,’ Earthshine said. ‘To emulate the signals I use to communicate with the Hatch. A simple hand-held thing … And I found a way to send signals through the emplacement substrate, so I will know, from my probe, when the final lid is opened.’

Stef was intrigued. ‘You sent signals through Hatch substrate material? That’s more than we ever managed, in the years I spent studying Hatches and kernels on Luna and Mars—’

‘They are gone,’ Earthshine said simply.

When it was safe, Earthshine opened the second door once more. The central chamber, with its door firmly closed once more, seemed entirely undamaged to Stef, and was completely empty.

Earthshine said that his probe had after all lasted a healthy fraction of a nanosecond, and it had learned a good deal about the nature of the ‘multiverse boundary’. It and the ColU immediately locked into a silent, high-speed electronic communication about the new data.

And Clodia and Chu, exploring the Hatch, found something new: grooves to take human hands, on the inner side of the Hatch’s second door. Three pairs of them.

‘That,’ the ColU said enigmatically, when it was told, ‘deserves further consideration.’

CHAPTER 72

Earthshine said, ‘I believe that the Dreamers have spoken to me as they have spoken to none other of our kind. And by “our kind” I mean complex life forms, equivalent to your own multicellular nature, although the details differ from world to world, biosphere to biosphere … That sounds arrogant, I know. Even grandiose.’

Stef said sceptically, ‘I’ll say. Of all that vast cosmic host—’

‘Yet I am unusual, for them. I am a product of human technology, of course. And yet I think that humanity itself, all of our biosphere above the level of the single-celled creatures, is a kind of technology to them. Created for a purpose, you see, or at least modified. But I am a secondary creation – as if one of my fabricators produced, not a copy of itself, but an entirely new design of its own. As such I am perhaps of – interest – to them. And I am not entirely under their control.’

‘As we are?’ Stef asked sourly.

‘Well, aren’t you?’

Titus grunted. ‘This all sounds too philosophical to me. What am I, a Greek?’ He, Stef, Beth, the ColU, the elders of this tiny antistellar colony, sat in a loose circle, beside the comfort of an open fire burning on a hearth of stone slabs, in the shadow of the strange spider-like structure that encompassed Earthshine’s support unit. Now Titus dipped his clay mug into the slowly boiling bowl of tea on the fire. ‘Face it, Earthshine. You got the Dreamers’ attention because you smashed Mars to pieces, and murdered a whole world of these clever animalcules in the process. That would get most people’s attention.’

‘Well, that’s true. And that, of course, was the intention.’

‘And so they brought you here,’ said the ColU, a glittering mass of technology set on a blanket away from the fire. ‘They guided you through their Hatch network to this place. And—’

‘And they spoke to me,’ Earthshine said, cutting in. ‘They told me their story. If that term is adequate for such a biography … In a way, you see, it is the story of life, in this universe.’

‘Tell us, then,’ Stef said, leaning forward, swathed in a blanket. ‘Tell us, Earthshine.’

‘From the beginning, even when the universe was still very young, there was life.

‘Life self-organised, from collections of more or less simple chemicals, blindly following the laws of chemistry and physics, guided by mathematical rules evidently inherent in reality. Microbial life, single-cell life, viral life … Some scientists used to think life could have emerged even when the Big Bang glow was still bright, and the whole universe was warm enough to be one big habitable zone.

‘On worlds with similar surface conditions, similar kinds of life emerged. Earth and Per Ardua, for example. But life spread, too, as rogue comets and asteroids blasted the surfaces of the young worlds, and handfuls of bugs buried deep in rock fragments survived chance journeys between the planets, and, more rarely, between the stars. Panspermia bubbles formed, worlds with similar conditions hosting related forms of life, sharing common origins. Across the galaxy such bubbles jostled, and even permeated; worlds of warm-Earth life could share stellar systems with worlds of cold-Titan life, as you’ve seen for yourselves.