It took the engineer a couple of minutes to catch up with the child, having paced for a while before making the decision to follow it. Even as she hurried after it, some small part of her nagged that she was making the wrong decision, that it was her duty to stay, or that it was safer to do so, or that she had no right to lay eyes upon the Gospel Wall.

But the much larger part knew what the child had been trying to tell her. Hers was a world of slavery; a world where the masses were designed so perfectly that they did not even think to have a choice, where it took a chance fault in their forms to kindle even the tiniest spark of free thought. Whatever the reasoning, whatever benefit the overseers drew from controlling a world like that, those few souls that wrested their will into their own hands had every right to look upon that wall and decide fate for themselves.

At the sound of her approaching footsteps, the child turned around, the side of its mouth curling up a little in an only slightly unconvincing imitation of a smile. She thought that a tad odd. Smiles were not something she would have imagined would be of much use to a war machine.

‘You will come to see the wall, then?’ it asked, the smile growing at her nod. ‘I am glad of that. I have heard that the wall is in the deepest vault, so we will head down.’

‘You know, if we get seen―’

It held up a hand. ‘We will do our best not to. If these overseers you fear so much come for us, they will remember that I am a war machine.’

She frowned, unconvinced by the child’s confidence, but said no more. For a while they walked in silence. Had she tried something like this alone, the engineer wouldn’t have had any idea where to go, but the child seeemed to have a route in mind. She began to wonder if it had found a map of the factory somewhere. She’d never heard of such a thing, but she imagined the child probably had a photographic memory; it would only take one look over to memorise the way down.

And they were moving down. As minutes turned into an hour, and one into two, the empty hallways brought them lifts from time to time. Some the child passed by with a dismissal glance; others it beckoned the engineer into and stood in still silence, its eyes fixed ahead, as the machine lowered them farther into the depths of the world. Sometimes the engineer’s conviction wavered, but each time she reminded herself: her fate was her own.

As they drifted into the third hour, a strange thought occurred to her. She glanced up and down the hallway they were passing through. Pipes stretched into the distance, the pale glow of the lights in the ceiling receding into gathering shadows the farther away they drew. The only sound was the low churning hum of machinery and the foosteps of the pair of pilgrims on the metal floor.

‘Where is everyone?’ she asked, a sudden fear rearing up to tickle the hairs on her neck. Granted, it was rare to pass someone in the Factory, but not this rare. ‘How do you know where to go? Which lifts to take?’

The child paused and looked down at her. ‘I cannot entirely explain it. I am a machine; I know other machines. This place is all metal and gear and fire and oil. The sounds, that shifting of steel…’ It placed a hand against the wall. ‘In a way it is like a call, or a whisper. It guides me as a map might guide you.’

It started walking again and the engineer followed suit, glancing over her shoulder once more. Now that she noticed how empty the halls were, something about it left an eerie chill on her; a strange thing to feel, given that the deeper they forged, the hotter the air grew.

‘What should I call you?’ asked the child.

It did not look at her as she pondered the question, so it did not see the frown on her face. ‘What do you mean?’

‘That wiring that tells me how to see fear, how to walk, how to talk. It tells me that most things in this world have names... though it does not tell me what mine is. What is yours?’

She shrugged. ‘I haven’t really got one. I have a number.’

‘What is your number?’

Sighing, she took a deep breath. ‘Eleven trillion, five hundred and thirty four million, twenty-one thousand, six-hundred and forty-five.’

For a moment the child spoke not a word, perhaps burning the number into that memory of its. ‘That number takes quite a while to say,’ it observed.

‘Well, I’m an engineer. There are a lot of us.’

‘Perhaps I should call you “Five”. From the last digit. Or “Neer”, as a short form of “engineer”.’

‘I don’t like “Five”.’

‘“Neer” it shall be.’

‘I don’t like that one either.’

It looked at her with a frown. ‘Then choose something yourself. Your fate is your own, why not your name? For my part, I will call myself “Bronze”. The metal is my skin, and I like the shape of the word.’

‘Mirror,’ she said.

‘For your name?’

She nodded.

‘It is a good one, I think.’

After that, quiet fell over them again. As they walked, Mirror turned her new name over and over in her head. It was not a thing she’d ever expected to have, or even truly thought about. Names were for things of importance; names were the Gospel, the Factory, the First Craftsmen; unique, powerful and recognised titles that represented the fundamental pillars of the world. Names were nothing short of sacred, so who was she to claim one for herself? She was just an engineer; the smallest of the small. The job she did was important but her, an individual, she was countless, replaceable. A single gear in a vast machine, so tiny that no one would ever notice if she stopped turning.

And who was this to her right? Another tiny thing with another name of its own. Bronze’s face was an enigma at that moment, its white eyes fixed ahead as it concentrated on following the way to the Gospel Wall. By rights, it should have been dead by now. It was less important than she was, due to step out onto a battlefield and fall only moments later, blasted apart by an explosion, wreathed in gunfire, or crushed beneath a falling building, its cold metal skeleton sinking into the mud and the blood and the oil, already forgotten by all the worlds.

But when she thought more clearly, she remembered that she had always been this way. No, she had not searched for the Gospel Wall before, she had not abandoned the principles of the Factory, she had not consciosuly decided to rebel against the overseers, but the seed had always been there, somewhere in her; without it, Bronze wouldn’t have convinced her. Years ago, she had taken that mirror. That was against the rules. But she’d wanted to.

As they descended yet another lift, those thoughts slowly faded into the background of Mirror’s mind to join the songs of the shifting machinery. Instead, something else came to the forefront as the rumbling of the gears in the walls sent them lower and lower. A slightly dizzy, tired feeling. It started slow, so small she barely noticed it, but grew gradually as the lift carried on down, until when they reached the bottom and it settled into place with a soft, metallic thump, she was standing with one hand against the wall, taking heavy breaths.

Bronze turned to beckon her and its eyes went wide. ‘What’s wrong?’

‘The air,’ she said. ‘Something’s not right about it. Too weak, I think. I can’t get enough breath out of it.’

‘We should turn back,’ Bronze decided, but she shook her head vigorously, soon regretting the idea, as the motion left her a little light-headed.

‘Not a chance,’ she told it. ‘I’ve already given up my life here. We’re going to see that wall. Lead the way.’

Bronze did not seem happy, but it did as it was told, placing her arm over its shoulders so it could support her as they pressed on. The darkness down here was stronger than anything Mirror had seen before. The shadows pervaded the air and loomed from the corners the faint and flickering lights didn’t reach. Perhaps it was those shadows that were tightening about her throat.

Their pace had slowed to a crawl by the time they came upon the dead end. The hallway expanded into a room larger than Mirror’s accommodation but far smaller than any assembly she had ever seen; in the far wall, three openings revealed chutes that led down into shadow and uncertainty. She stopped, a glimmer of realisation dawning in her tired mind.

Letting go of her, Bronze stepped forwards, a frown fluttering over its eyes. ‘Where is the wall? I followed the path, your Gospel Wall should be here.’

‘I should’ve thought of this,’ Mirror said, leaning against the wall again. ‘The machines are all part of the Factory, of course they wouldn’t lead you to the Gospel Wall. Trusting them, it’s like trusting the overseers. This is… this waste disposal. That’s why the air’s bad, that’s why it’s so empty. They only send machines down here, twice a changeover.’

‘But the machines… they weren’t speaking. They didn’t have intent. I just listened. To where they were. To their shapes, their sizes, how far away they were.’

‘This place lies,’ Mirror said.

Bronze turned around, anger on its face for the first time. Mirror wondered briefly where it had seen that emotion in order to copy it, but there was no time to think about things like that. Bronze’s gaze settled on something behind her, its eyes widening, and it adopted a defensive stance. Turning slowly, still holding herself up with the wall, she followed its gaze and laid eyes on, arms folded, flanked by two enforcers, an overseer.