original choice.
‘I just want to be careful, that’s all,’ she said. ‘We can’t assume anything. They might think from right to left, so that the figures on the right form the sequence which those on the left are supposed to complete. Or they might think diagonally, or something even less obvious.’
Childe nodded. ‘And the obvious choice might not always be the right one. There might be a deeper sequence — something more elegant — which we’re just not seeing. That’s why I wanted Celestine along. If anyone’ll pick out those subtleties, it’s her.’
She turned to him. ‘Just don’t put too much faith in whatever gifts the Jugglers might have given me, Childe.’
‘I won’t. Unless I have to.’ Then he turned to the infiltration specialist, still standing by the frame. ‘Hirz — you may go ahead.’
She reached out and touched the frame, covering the eleven-sided figure with her palm.
After a heart-stopping pause there was a clunk, and I felt the floor vibrate even more strongly than it had before. Ponderously, the door slid aside, revealing another dark chamber.
We all looked around, assessing each other.
Nothing had changed; none of us had suffered any sudden, violent injuries.
‘Forqueray?’ Childe said.
The Ultra knew what he meant. He tossed the float-cam through the open doorway and waited several seconds until it flew back into his grasp.
‘Another metallic chamber, considerably smaller than this one. The floor is level with the door, so we’ll have gained a metre or so in height. There’s another raised door on the opposite side, again with markings. Other than that, I don’t see anything except bare metal.’
‘What about the other side of this door?’ Childe said. ‘Are there markings on it as well?’
‘Nothing that the drone could make out.’
‘Then let me be the guinea pig. I’ll step through and we’ll see what happens. I’m assuming that even if the door seals behind me, I’ll still be able to open it. Argyle said the Spire didn’t prevent anyone from leaving provided they hadn’t attempted to access a new room.’
‘Try it and see,’ Hirz said. ‘We’ll wait on this side. If the door shuts on you, we’ll give you a minute and then we’ll open it ourselves. ’
Childe walked up the three steps and across the threshold. He paused, looked around and then turned back to face us, looking down on us now.
Nothing had happened.
‘Looks like the door stays open for now. Who wants to join me?’
‘Wait,’ I said. ‘Before we all cross over, shouldn’t we take a look at the problem? We don’t want to be trapped in there if it’s something we can’t solve.’
Childe walked over to the far door. ‘Good thinking. Forqueray, pipe my visual field through to the rest of the team, will you?’
‘Done.’
We saw what Childe was seeing, his gaze tracking along the doorframe. The markings looked much like those we had just solved, except that the symbols were different. Four unfamiliar shapes were inscribed on the left side of the door, spaced vertically. Each of the shapes was composed of four rectangular elements of differing sizes, butted together in varying configurations. Childe then looked at the other side of the door. There were four more shapes on the right, superficially similar to those we had already seen.
‘Definitely not a geometric progression,’ Childe said.
‘No. Looks more like a test of conservation of symmetry through different translations,’ Celestine said, her voice barely a murmur. ‘The lowest three shapes on the left have just been rotated through an integer number of right angles, giving their corresponding forms on the right. But the top two shapes aren’t rotationally symmetric. They’re mirror images, plus a rotation.’
‘So we press the top right shape, right?’
‘Could be. But the left one’s just as valid.’
Hirz said, ‘Yeah. But only if we ignore what the last test taught us. Whoever the suckers were that made this thing, they think from left to right.’
Childe raised his hand above the right-side shape. ‘I’m prepared to press it.’
‘Wait.’ I climbed the steps and walked over the threshold, joining Childe. ‘I don’t think you should be in here alone.’
He looked at me with something resembling gratitude. None of the others had stepped over yet, and I wondered if I would have done so had Childe and I not been old friends.
‘Go ahead and press it,’ I said. ‘Even if we get it wrong, the punishment’s not likely to be too severe at this stage.’
He nodded and palmed the right-side symbol.
Nothing happened.
‘Maybe the left side… ?’
‘Try it. It can’t hurt. We’ve obviously done something wrong already.’
Childe moved over and palmed the other symbol on the top row.
Nothing.
I gritted my teeth. ‘All right. Might as well try one of the ones we definitely know is wrong. Are you ready for that?’
He glanced at me and nodded. ‘I didn’t go to the hassle of bringing in Forqueray just for the free ride, you know. These suits are built to take a lot of crap.’
‘Even alien crap?’
‘About to find out, aren’t we?’
He moved to palm one of the lower symmetry pairs.
I braced myself, unsure what to expect when we made a deliberate error, wondering if the Spire’s punishment code would even apply in such a case. After all, what was clearly the correct choice had elicited no response, so what was the sense in being penalised for making the wrong one?
He palmed the shape; still nothing happened.
‘Wait,’ Celestine said, joining us. ‘I’ve had an idea. Maybe it won’t respond — positively or negatively — until we’re all in the same room.’
‘Only one way to find out,’ Hirz said, joining her.
Forqueray and Trintignant followed.
When the last of them had crossed the threshold, the rear door — the one we had all come through — slid shut. There were no markings on it, but nothing that Forqueray did made it open again.
Which, I supposed, made a kind of sense. We had committed to accepting the next challenge now; the time for dignified retreats had passed. The thought was not a pleasant one. This room was smaller than the last one, and the environment was suddenly a lot more claustrophobic.
We were standing almost shoulder to shoulder.
‘You know, I think the first chamber was just a warm-up,’ Celestine said. ‘This is where it starts getting more serious.’
‘Just press the fucking thing,’ Hirz said.
Childe did as he was told. As before, there was an uncomfortable pause which probably lasted only half a second, but which felt abyssally longer, as if our fates were being weighed by distant judicial machinery. Then thumps and vibrations signalled the opening of the door.
Simultaneously, the door behind us had opened again. The route out of the Spire was now clear again.
‘Forqueray…’ Childe said.
The Ultra tossed the float-cam into the darkness.
‘Well?’
‘This is getting a tiny bit monotonous. Another chamber, another door, another set of markings.’
‘No booby-traps?’
‘Nothing the drone can resolve, which I’m afraid isn’t saying much.’
