Arthur let his hand fall onto his own wrench, and he tensed a little, ready to draw.

‘I reckon you must be some sort of short Denizen spy for the Big Boss. It’s bad enough having the Sorcerous Supernumeraries following us about, without a spy among us. So it’s time for you to—’

Arthur blocked her sudden swing at his legs with his own wrench. Sparks flew as the silver tools met. Alyse let go of the ring and struck again, a two-handed blow that would have overcome any normal Piper’s child. Arthur met it one-handed, and it was Alyse who reeled back and would have fallen if Arthur hadn’t hooked his foot around her ankle just before she went over.

‘I’m not a spy!’ Arthur shouted. ‘Or a Denizen!’

Alyse grabbed hold of the ring again and eyed him warily.

‘What are you, then?’

‘I’m Arthur, the Rightful Heir of the Architect. I’ve come here to find and free Part Six of the Will.’

‘No, you’re not!’ exclaimed Alyse. ‘Arthur’s eight feet tall, and he’s got a pointy beard down to his waist!’

‘Those stupid books!’ groaned Arthur. Some Denizen (or group of Denizens) somewhere in the House was writing and distributing very much fictionalised accounts of Arthur and his activities in the House. ‘Those books are all lies. I really am Arthur.’

‘You are very strong,’ said Alyse. ‘And you are more like us than a Denizen . . . no pointy beard, hey?’

‘No.’

‘If you are Arthur, then you’re an enemy of the Big Boss, right?’

‘If you mean Superior Saturday, yes I am.’

‘Who doesn’t trust us anymore, on account of the Piper being out and about again.’

‘Yes. Neither does Dame Primus – I mean, the Will of the Architect. The Parts I’ve already gathered, that is. But I trust you. I mean I trust Piper’s children in general. In fact, I reckon the children are the smartest and most sensible people of anyone in the whole House.’

‘That’s true,’ Alyse agreed easily. ‘But speaking for the gang, we don’t care for politics. We just want to get our work done.’

‘I’m not going to interfere with your work,’ Arthur promised. ‘Just don’t report me. As soon as I can figure out where the Will is, we’ll be off.’

‘That Suze who’s with you – she really is a Piper’s child, isn’t she?’

‘Yes.’ Out of the corner of his eye, Arthur saw that they had passed the empty office blocks, and the cubes were all full of green lamps and working Denizens again. Only here the umbrellas were all orange.

Alyse looked at Arthur thoughtfully.

‘I suppose we could just go along with it for today,’ she said. ‘I mean, accept you for what you say you are. If there’s any trouble, I’ll act as surprised as anyone.’

‘That’d be great!’ exclaimed Arthur. ‘I just need some time to track down the Will. I’ll stay out of your way.’

‘Just do your work,’ said Alyse. ‘Otherwise it’ll look suspicious. You can sneak out of the depot tonight. I want you gone before morning.’

‘Very well,’ said Arthur. ‘Hopefully I’ll know where I need to go by then.’

‘You don’t know where this Will is?’

‘No. But the Will can speak inside my mind, tell me how to find it. I’ve already heard it twice. I heard it just before we got on this chain, when all that water splashed on my head.’

‘There’s always a lot of splashes,’ said Alyse. ‘The full sorcerers, up above 61000, they like to play games, weave spell-nets to catch the rain and then let it all go at once on their inferiors below. Can be dangerous. We’ve lost a few workers, washed right out of an office and into a shaft, or even out of one side.’

‘It’s odd,’ said Arthur. ‘This constant rain. I mean, the weather was broken in the Middle House, but it must be on purpose here, since Superior Saturday has all her sorcerers to fix it.’

Alyse shrugged. ‘It’s just the way it’s always been,’ she said. ‘Least for the last ten thousand years. Same as when the Boss started building this tower.’

‘Ten thousand years?’ asked Arthur. ‘It’s been raining for ten thousand years in House time? How do you know? Haven’t you been washed between the ears?’

‘Course I have,’ said Alyse. ‘That’s what the Denizens say. They’re always talking about the plan, and building the tower, and how it’s been ten thousand years, and if only the tower would reach the Gardens, then the rain will stop and all that. Look, there’s the Drasil again – we’re going through the seven hundreds.’

‘Reach the Gardens?’ asked Arthur. ‘The Incomparable Gardens? That’s what Saturday is trying to do?’

‘That’s what the sorcerers say. We just do our job. Can’t be worrying about all the top-level stuff and plans and that.’

‘What is a Drasil?’ Arthur looked through the empty, spare structure of the tower at the distant, vertical line.

‘A very, very big tree. There’s four Drasils. They hold up the Incomparable Gardens and they’re always growing. I don’t know how high they are, but everyone says the tower is not even close.’

‘Maybe the rain makes them grow,’ said Arthur.

‘Maybe.’

Arthur kept looking at the Drasil until they passed through the empty section and the view was once more obscured by thousands of offices. Alyse didn’t talk, but that suited Arthur. He had a lot to think about.

The rain is important, he thought. It must be, if it started ten thousand years ago, when the Trustees broke the Will. I wonder if it’s Sunday who makes it rain, for the Drasil trees? But that couldn’t be right, because Saturday has the Sixth Key, and it would be strongest here . . . only I kind of remember someone saying the Seventh Key was paramount or the strongest overall or something like that . . .

‘We’re coming up to the eight hundreds.’

Alyse’s voice interrupted Arthur’s train of thought. He looked out and wondered how she knew what level they were at. Then he saw green umbrellas everywhere, in many different shades. The sorcerers, or would-be sorcerers, had umbrellas of dark green, bright emerald green and lime green, as well as ones that had graduated washes of green and patterns of green.

‘Green umbrellas in the eight hundreds,’ said Arthur. ‘That’s how you know where we are – from the colour change in the umbrellas.’

‘Yep,’ Alyse confirmed. ‘Yellow at nine hundred, then you count. There are numbers on the framework, but they’re too small and hard to read from the Big Chain. Now get ready – we’ll have to step off in a minute.’

She took his hand again and they shuffled to the edge of the link. The offices were flashing past very swiftly, Arthur thought. Suddenly the umbrellas changed to yellow. He glanced at Alyse and saw her lips moving as she counted. He tried to count too, but couldn’t keep up.

‘Eighty-five – get ready!’ snapped Alyse.

Arthur started counting again in his head.

‘Ninety-four! Go!’

They stepped off the link, Alyse dragging Arthur, timing it to perfection so that it felt like no more dangerous than stepping down from a high kerb.

‘Move!’ Alyse snapped again. Arthur followed her, splashing past the desk and its oblivious Denizen under his yellow umbrella.

‘Got to make room,’ explained Alyse as she led the way through to a neighbouring office. Behind them, two more grease monkeys stepped off the link and quickly moved diagonally through to an adjacent office.

Arthur looked around and noticed that for the first time, the Denizens at their desks were covertly watching the grease monkeys. While most of them were continuing to write with both hands, they all slowed down to get a better sidelong look.

‘Why are they watching us?’ Arthur whispered to Alyse.

‘Because they know we’re here to shift someone up or down,’ said Alyse loudly. She glared at the Denizen behind the desk next to her. He immediately looked back at his shaving mirror screen and his writing sped up.

‘Right,’ said Arthur. More grease monkeys stepped off the chain and one waved as they splashed their way across. It was Suzy, who looked like she was enjoying herself. He waved back, and learned that he shouldn’t tip his head back when doing so, because a sheet of rain fell on his face.

Alyse had her notebook out again and was studying an entry, her finger moving along the lines. Arthur noticed that all the closer Denizens were watching intently despite Alyse’s earlier glaring.

More grease monkeys arrived in pairs and moved through the offices, until the last, Whrod, stepped off alone.

Alyse shut her notebook with a snap and pointed deeper into the tower.

‘This way!’ she declared.

‘Is it a promotion?’ asked a Denizen. He had given up all pretense of work, and was staring at Alyse, his mouth twisted up in an ugly expression that didn’t match his handsome features.

Alyse ignored him. Striding through a waterfall that had just started coming down, she led the gang deeper into the tower, pausing every now and then to check the numbers that were embossed on the red iron posts that made up the framework of the building.

As the grease monkeys marched, Arthur heard the Denizens whispering all around them.

‘Promotion . . . it must be . . . promotion . . . who is it . . . promotion . . . anyone see a purple capsule . . . - promotion . . . promotion . . .’

‘There she is, four offices ahead,’ Alyse whispered to Arthur. ‘With the saffron checks on the darker yellow. You wait here and join Whrod – he’ll tell you what to do. And look out.’

‘For what?’ asked Arthur.

‘The others will throw things as soon as they know it’s a promotion. Wait for Whrod now.’

Arthur nodded and stopped where he was. Whrod was close behind, and the other grease monkeys were approaching in an extended line across a dozen offices.

‘Go!’ shouted Alyse. She ran ahead to the chosen office, jumped on the desk, and then from there to a corner of the cube. Holding on to the frame with one hand, she started working on something with a wrench.

The Denizen stood up and folded her yellow umbrella. It turned black as it closed. Then, as she reopened it, a rich purple colour spread in swirls across the fabric like oil in water. She propped the umbrella up, then quickly climbed under the desk, calling out as she did so.

‘Goodbye, idiots! Long may you labour in vain!’

As the other grease monkeys swarmed over to the office, Arthur ran with Whrod to the lower-left corner. Whrod had his wrench out and started working on a large bolt that fastened the office cube to the framework. Arthur didn’t know what he was supposed to do. He drew his wrench but only stood there until Whrod looked up at him angrily.

‘Come on! Get the other side!’

The restraining bolt went through the frame and was fastened on the other side with a large hexagonal bronze nut. Arthur got his wrench onto it as Whrod turned the bolt and drew it free.

Arthur caught the nut as it fell, just before it disappeared through the latticed floor.

‘Next one up!’ Whrod called out, immediately going to another bolt a foot up from the first. Three other teams of grease monkeys were undoing the bolts in the other corners, and more were working above and around the office, some of them standing on each other’s shoulders and some even hanging by their fingers from the latticed floor above, like real monkeys.

‘Booklicker!’ shouted a nearby Denizen.

‘Toady!’

‘Slithering sycophant!’

‘You stole my promotion!’

All the Denizens in the nearer offices were shouting, waving their umbrellas, and becoming very obstreperous.

‘Hurry!’ snapped Whrod. ‘They’ll start throwing things in a second.’

As Arthur crouched to get his wrench positioned, something hit him hard in the back and fell at his feet. He looked down and saw it was a broken teacup. Then a saucer smashed into pieces in front of his face, the debris falling on Whrod’s back.

‘Lower East bolts clear!’ shouted a grease monkey.

‘Lower West bolts clear!’

‘Lower North bolts clear!’

‘Darn it,’ spat Whrod. ‘Last. Got the nut? Lower South bolts clear!’

His declaration was echoed by the teams working on the ceiling and by shouts that came from higher up. Arthur looked and saw that there were other gangs on the higher floors, and, amid them, several dull bronze automatons that looked like ambulatory jellyfish, round three-foot-diameter globes that stood five feet tall and walked on four or five semirigid tentacles while they wielded tools in their other numerous appendages.

‘Check chain!’ shouted Alyse.

Whrod used the edge of his wrench to peel back what Arthur had thought was a solid part of the vertical frame, but was in fact a red-painted cover or lid that fitted snugly on the beam. Under it, there was a smaller version of the Big Chain, big fat links four or five times the size of a bicycle chain. The chain ran on the inside of the U-shaped vertical beam, though it was not moving now.

‘Chain present – looks all right!’

Diagonally opposite, another grease monkey confirmed that the chain was present there.

Alyse looked up, cupped her hands around her mouth, and shouted, ‘Ready to rise! Shift them aside!’

Arthur looked up too, completely in the moment, all his troubles and responsibilities forgotten, replaced by curiosity as he wondered what exactly was going to shift aside.