‘Commence paddling!’ ordered Jarrow.

Arthur and Fred mechanically took up their oars again and dipped them into the water. The raft, having stopped, was very difficult to get moving again. Fortunately it was not far to the water-gate, a grilled gate of old iron some thirty yards farther along the bastion’s lake wall.

This portcullis was raised just enough to allow them to get the raft and themselves through and into a flooded chamber within the bastion. The grille came crashing and splashing back down as soon as they were inside.

There was just enough room inside to paddle the raft to a spot between two small boats, which were tied up against a low wooden quay or wharf.

There was a reception party arrayed along the wharf: a lieutenant, a corporal, and two dozen Denizens in regimental scarlet, with bayonets fixed to their Nothing-powder muskets. Jarrow climbed up and, after an exchange of salutes and the presenting of arms, talked quickly with the other lieutenant. Arthur and Fred wearily gathered up all the gear and Not-Horse harnesses.

‘Gold! Green! Leave that!’ instructed Jarrow. ‘We have to report to Marshal Noon’s headquarters. You’re the last two Piper’s children to arrive.’

Arthur and Fred looked at each other and happily dropped the saddles, saddlebags, and other gear. Then they helped each other climb up onto the dock, remembering to salute the other lieutenant.

‘Better get ’em in Regimentals before they go to the Marshal,’ said the other officer. ‘Unless they’re permanent Troopers.’

‘They aren’t yet,’ said Jarrow. He clapped Arthur and Fred on their sore backs, and they both nearly fell over from the sudden pain. ‘But they have the makings. Let’s be off. Troopers, atten-hut! By the left, quick march!’

Jarrow obviously knew the Citadel well. From the water-gate, he led them up a ramp and out onto the top of the bastion. They marched along its length, passing sentries and cannons, all staring out. Then they passed through a guardhouse with some formality between Jarrow and the officer of the watch, continued down another ramp and along a covered walkway lined with small cannons on swivels, climbed up through another guardhouse, went down a spiral staircase, marched across a cleared space between the third and second defence lines, entered another bastion, and ultimately found themselves in a Quartermaster’s Store that was so identical to the one at Fort Transformation that the two weary Piper’s children wondered if they’d ever left.

In the space of fifteen minutes their Horde hauberks and helmets were stripped off and replaced by the much lighter and more comfortable scarlet tunics, black trousers, and pillbox hats of the Regiment. They were issued familiar white belts with pouch and bayonet frog, and bayonets but not muskets.

‘Only got powder for the sharpshooters,’ said the Quartermaster Sergeant, a grizzled Denizen who had at some time been shot through the cheeks with a Nothing-laced bullet, so the wound would not completely heal. As he spoke, air sucked through the holes and made it hard to understand his speech.

Jarrow did not change, presumably because he was a permanent Horde officer, but he did take the time to give his armour and boots a quick clean, earning the Quartermaster Sergeant’s approval for doing it himself. Then he waited patiently while Arthur and Fred got sorted out. When they started to examine their bayonets, he called them to attention and marched them out again.

This time, they left the outer bastions behind, crossing the bare area to the second line and taking a zigzag path along various ramps, through several guardhouses, and up four sets of stairs. On the far side of the second defence line, they crossed an even wider expanse of bare earth and a greater complexity of ramps, stairs, and guardhouses before exiting the third-line bastion to arrive at the bottom of a narrow stair that wound its way up the side of the white stone hill.

‘Where are we going, sir?’ asked Fred.

‘Marshal Noon’s headquarters are in the Star Fort,’ said Jarrow. ‘Up these stairs, now!’

The hill was not as high as Arthur had thought it was when he’d been out on the lake. Perhaps no more than three hundred feet. He felt so much better after shedding the heavy weight of the hauberk, helmet, and lightning-charged tulwar that it was almost a pleasure to climb the steps, though he knew he would be sore later. His time in the Army of the Architect had helped him discover numerous muscles he had not previously known he had; unfortunately this discovery was always painful.

The bastions of the Star Fort were smaller versions of the ones in the lower defence lines. At the top of the stairs, Jarrow called out and did not proceed until he was answered by the sentry. Then, clearly illuminated by the greenish moonlight, they marched across the bare earth, crossed a ditch on a gangplank, and entered a sally port in the face of the bastion.

‘Reckon you could find your way out of here?’ asked Fred a little later, as they waited for Jarrow to finish talking to yet another lieutenant in yet another guard room – though this one was nicer than the ones below, as it had panelled wood walls rather than bare stone, and a blue-and-red carpet on the floor.

‘No,’ said Arthur. That thought had occurred to him too, probably because it was quite possible he, unlike Fred, might really need to get out again.

‘You’re going into Marshal Noon’s reception room,’ said Jarrow, turning back to them. ‘Apparently there’s already a number of Piper’s children waiting, and the Marshal will address you soon. Remember to stand at attention at all times unless ordered otherwise, and do not speak unless you are spoken to. Is that clear?’

‘Yes, sir!’ shouted Fred and Arthur.

Jarrow winced.

‘You don’t have to shout like that here. Save it for the parade ground. You’ve done well, Green, and you too, Gold. Good luck for the future. I hope we serve together again.’

He shook hands with them and was gone. Arthur and Fred turned nervously to the other door. A corporal grinned at them and opened it, gesturing for them to go inside.

Arthur felt an anxious, fluttering pain in his stomach. It didn’t look like this was going to be the prelude to Sir Thursday revealing his identity and doing something horrible to him. But he was nervous about whatever was to come, for it was an unknown, both to his soldier self and his secret role as the Rightful Heir.

They marched in together in perfect step. The room was large but not as expansive as the round-table room in Monday’s Dayroom. This room was much more spartan. It had a polished timber floor, with a spindly-legged desk in one corner, a black lacquered standing screen with maps pinned to it, several weapons mounted on the walls, and the preserved head of a monster – possibly a fish, as it looked like it might have come off a thirty-foot-long piranha. There were also twenty Piper’s children in two ranks of ten, standing at ease. Most were in scarlet Regimentals, but there were four Legionaries in dress armour, three grey-coated Artillerists, and two Borderers in green. They all turned their heads to look as Fred and Arthur entered the room and marched over to form up on the left of the parade.

‘Wait for it,’ whispered Arthur as they neared the ranks. ‘Fred and Ray, halt! Left turn!’

They executed the movements perfectly. The other Piper’s children looked to the front again. All except for one of the Borderers, who stepped back behind the parade and sidled down the line. Then she came over and stood at attention next to Arthur.

‘Hist! Arthur!’

Arthur slid his eyes to the left. The Borderer, a corporal no less, was Suzy!

Arthur’s head moved two inches in sheer surprise before he whipped it back in place. Even so, his eyes nearly left their sockets with the effort of peering at his friend. He felt incredibly relieved by her appearance and at the same time his anxiety ratcheted up a notch. Suzy’s arrivals normally anticipated serious mayhem and difficulties only by minutes.

‘Suzy! They let you join after all?’ he whispered out of the corner of his mouth. ‘And you’ve already made corporal?’

‘Not exactly,’ said Suzy. ‘It’s a bit complicated, but basically I got here, and they had a bit of trouble working out what to do with me. For a couple of hours they were going to shoot me as a spy. But it turns out I was in the Army before. I did my hitch four hundred years ago and have been in the Reserve ever since! Not that I can remember it, though a few bits and pieces are coming back now. I told them I’d just got cleaned between the ears and was a bit confused, and then this order came for all Piper’s children to report, no exceptions, so the major who was in charge said ‘good riddance’ and sent me along. The important thing is, Arthur, I’ve got the –’

‘Atten-hut!’

An immaculate Regimental Sergeant-Major, her scarlet sleeves adorned with laurel wreaths and crossed swords, had entered the room. She marched over to the Piper’s children, ramrod-straight, her boots clicking in perfect rhythm on the floor, a silver-pointed ebony pace-stick under her arm.

‘Close up that gap, soldier!’ she snapped, pointing to the hole Suzy had left. She halted in front of the two lines, did an about-turn, and saluted the Denizen who had just followed her in.

He was considerably less splendid than the RSM, wearing what looked like exactly the same kind of Regimental private’s uniform as Arthur’s, with the addition of two black epaulettes that were each adorned with a circle of six tiny golden swords. This struck Arthur as odd, since the Recruit’s Companion said a marshal was only supposed to have five. The only other alteration to the private’s uniform was that instead of a pillbox hat he wore a kind of black beret with a golden sword badge pinned to it. The badge looked too big for the beret, depicting a very old-fashioned hand and a half sword, with a serpent coiled around the hilt.

He had small, deep-set eyes and was not particularly handsome for such a superior Denizen. He wasn’t all that tall either, being only six foot six or so, and was perhaps half as wide across the shoulders as Sergeant Helve. All in all, he was not physically intimidating. But there was something about those dark eyes, the flat-lined mouth, and the lift of his chin that made Arthur immediately fear him.

‘Stand them at ease,’ this Denizen ordered the RSM.

‘Stand at ease!’ repeated the RSM at several times the other Denizen’s volume.

The Piper’s children stood at ease, none of them out of time. Even Suzy got it right.

‘I am Sir Thursday,’ said the Denizen. The faintest ripple went through the ranks as he said that, but no more.

Arthur stared at the air in front of him, not even daring to move an eyeball. But though his body was still, his mind was racing, trying to work out what might happen and what he could do.

‘I am going to explain to you a plan I have,’ continued Sir Thursday. ‘Then I am going to ask for volunteers.’

He paced up and down as he spoke, then suddenly stopped and looked out the window on the far side of the room.

‘Marshal Noon was to explain the plan, but he has suffered an indisposition. He may be joining us later. Sergeant-Major! The mapboard.’

The RSM marched across the room and picked up the black screen, carrying it back to a position in front of the Piper’s children. Then she marched around to stand near Suzy, so she could also watch the presentation.

Sir Thursday walked over to Arthur and took the bayonet from the bayonet frog on Arthur’s belt. Arthur didn’t move and didn’t look, even as he heard the foot-long blade slide free.

Surely he won’t stab me in front of everyone, he thought desperately. Dame Primus said he would obey his own regulations. He won’t stab me – ‘I shall borrow this for a moment, Private,’ said Sir Thursday. ‘To use as a pointer.’

He turned to the mapboard and flourished the bayonet.

A glowing yellow line appeared where he indicated, and another. Quickly, Sir Thursday sketched a square.

‘This is the Great Maze,’ he said. He added an X down in the lower right corner. ‘This is the Citadel.’

Then he drew a small circle right in the middle of the square.

‘And this is the absolute centre of the maze, a point called five hundred/five hundred. Who can tell me the only possible way to get a strike force from the Citadel to point five hundred/five hundred by midnight tonight, given that the tiles have stopped moving? It is three hundred miles away and there are perhaps two hundred and fifty thousand New Nithlings in the way.’

He turned to face them.

‘Anyone? How about you, Private? Green, isn’t it?’

‘Yes, sir,’ croaked Arthur. He wasn’t sure if he should play stupid or give an honest answer, because he had immediately thought of one way to get there. ‘I suppose … that the only way would be via the Improbable Stair.’

‘And the natural conclusion one would draw from that?’

‘That very few … uh … Denizens even know about the Improbable Stair, and fewer still can travel it,’ said Arthur. He had a bad feeling about where this was going. ‘I don’t know how many soldiers someone able to use the Improbable Stair could take with them.’

‘Very good,’ said Sir Thursday. ‘You are commissioned herewith as Second Lieutenant Green. In the Regiment, unless you have a preference for the Horde.’

‘No, sir,’ said Arthur.

What is he up to? he wondered. He’s setting me up for something.

‘The obvious question is, why would a force need to be sent from the Citadel to point five hundred/five hundred?’ Sir Thursday continued. He started to tap the mapboard with the bayonet. ‘The answer is simple. Because ultimately I must obey my political superiors in the House, this campaign year I was compelled to change my plans and allow a vast number of Nithlings into the Great Maze. Nithlings who, unbeknownst to me, are New Nithlings, practically Denizens. They are trained, disciplined, and well-equipped, and they are led by someone powerful and very clever, someone probably assisted by traitors within my very staff, someone who has uncovered one of the secrets of the Great Maze and with a lot of treacherous help has managed to put a great big spike of stabilised Nothing straight into the master position at point five hundred/five hundred!’