The disorganisation was reflected in many of the discussions Arthur overheard, which were often arguments. He heard one woman refusing to sign for forty-six assorted descriptions on calfskin, and another hotly disputing that she was responsible for the Aaah! to Aaar volume of the Loose-leaf Registry of Lesser Creations.

A crowd of men and women at the door of one building were arguing with a very tall man in a blue uniform coat who stood in the doorway and wouldn’t let them in as he read from a scroll in his hand about some sort of failure to renew a licence.

Another crowd was picking up the pieces of a huge stone tablet that had apparently toppled out of an upper-storey window, which was itself crumbling away. Two men walked around a pile of dropped papers, both loudly disclaiming any responsibility for them as they blew away down the street. Arthur noticed that these papers were rapidly picked up by some of the more ragged children, but when he tried to see where they went with them, he lost them in the crowd.

Every building appeared to be an office of some kind. At least, every one Arthur looked closely at, hoping to find something else, like a café, a restaurant, or a supermarket. Not that he was hungry. He just wanted to see something normal.

All the buildings had bronze plates or small signs on the doors or next to them, but almost all of these were so covered in verdigris that Arthur couldn’t make out what they said. The few that were bright and polished made no sense to him. He saw signs that read SUB-BRANCH SECOND DIRECTORATE OF THIRD DEPARTMENT OF INTERIOR RATIOCINATION AND CROSS-CHECKING – LOWER ATRIUM OFFICE AND WHAT GOES UP NEED NOT COME DOWN INITIATIVE OFFICE – LOWER ATRIUM ANNEX AND INQUISITOR GENERAL’S ELEVENTH DEPUTY ASSOCIATE ASSISTANT IN CHARGE OF WINGS – LOWER ATRIUM INSPECTION OFFICE.

Another aspect of the disorganised bustle was that everyone ignored Arthur. In his too-large shirt and watch cap, he didn’t look much different from the other children. But the kids kept their distance from him, and he knew it was on purpose.

He tried to talk to a woman who looked less busy than most, but as soon as he went up to her and said, ‘Excuse me,’ she jumped into the air, pulled a sheaf of papers from her sleeve, and held them up close against her face, reading aloud so rapidly that Arthur couldn’t understand a word.

He made his second approach to a very old man who was slowly walking up the street, holding a basket full of tiny gold tablets. Arthur fell in step with him and said, ‘Excuse me’ once more.

‘It’s not my fault!’ exclaimed the old man. ‘The Lower Supernumary Third Archive deposit hatch is shut and no Archivist on duty these last thousand years. Tell that to your superior.’

‘I just wanted to ask –’ Arthur started to say. But before he could finish, the old man put on a startling turn of speed and pushed through the crowd. His passage provoked a storm of minor accidents and complaints, and soon the whole street was strewn with dropped papers, people banging their heads together as they tried to pick them up, and others falling over at least a thousand lead pencils that had rolled out of an overturned tub.

Arthur stared at the chaos and decided he needed to think about his next approach. He climbed up the steps of the closest office and leaned back on yet another verdigris-obscured brass plate. As he had done every few minutes, he felt through his shirt to confirm that the Key was still at his side.

Just as he touched it, there was a sudden increase in noise from the street. The angry shouts and cries and arguments suddenly changed tone. There were cries of alarm and genuine fear. Instead of milling around, the crowd parted and fled in opposite directions. Many of them were shouting, ‘Help!’ and ‘Nithlings!’

Arthur stopped leaning and stood up straight to see what was happening. The street had completely cleared in a matter of seconds. A few sheets of paper drifted across the cobbles and fell into the cracks, and a large ox-hide parchment with red ochre pictograms flapped where it had been abandoned a moment ago.

Arthur could see no reason for the panic, but he could smell something.

A familiar odour. The rotten-meat smell of the Fetchers’ breath.

Then he saw that the cracks in the street were slowly spreading and widening, and a thin mist of dark vapour was spraying up, as if oil had been struck under the cobbles.

A whistle sounded in the distance, sharp and shrill. It was answered by others, coming from every direction. As if in reaction to the whistles, the cracks in the street groaned open even wider, and more streams of dark vapour fountained up.

The vapour plumes grew till they were six or seven feet high, then the black mists began to solidify into semi-human shapes. Misshapen men and women formed out of the gas, creatures whose faces were on backwards, with double-jointed arms and patches of scales upon their skin. Imperfect copies of the clothing worn by the paper-shufflers of the city formed upon them too – coats with sleeves missing, and hats with no crowns, and trousers where one leg was three feet longer than the other and trailed upon the ground.

The plume Arthur had spotted first was also the first to be fully formed. It became a sticklike sort of man-thing with rubbery arms that hung down past its knees. It had one red-rimmed eye in the centre of its forehead and it wore a single garment rather like a blue straitjacket that was tied at the back, a crushed top hat with a gaping hole in the crown, and spurred boots of different sizes.

Arthur stared at it in horror, and the thing stared back, one transparent eyelid slowly sliding up and down across his single red-rimmed eye. Then it opened its mouth to reveal yellowed canine fangs and a forked tongue that flickered in and out.

Arthur realised he should have run when everybody else did. He started down the steps, but the thing was already at the bottom, and its six brethren were assuming solid form behind it.

Ten

ARTHUR RETREATED UNTIL his back was up against the door. He pushed on it with his shoulder, but it didn’t move. Without taking his eyes off the creature, he reached behind to frantically twist the doorknob, but it wouldn’t turn either. There was no escape that way.

Quickly Arthur looked from side to side, seeking some other way out. But the misshapen creatures had spread out to cover the neighbouring buildings, and the one-eyed horror was limping up the steps. It drooled as it came and licked its lips, its one eye looking hungrily at the boy.

‘Get back!’ shouted Arthur. He pulled out the Key, got it tangled in his shirt for a heart-stopping moment, then held it ready like a dagger.

The one-eyed creature hissed when it saw the Key. It turned its head and its misshapen mouth quivered. It stopped its advance and called out to its companions, who had been spreading out down the street. Arthur wished he didn’t understand its guttural speech, but he did.

‘Treasure! Danger! Come and help me!’

All of the creatures stopped and turned back towards Arthur. The one-eyed one hissed again and began to slink forward, much more carefully this time, its eye focused not on Arthur, but on the Key. The clock hand was glowing again, Arthur saw, light gathering at the point. The Key was gathering its power as the creature gathered its allies.

The one-eyed creature suddenly crouched and Arthur knew it was about to spring. He pointed the Key at it and shouted, a wild cry that wasn’t a word at all, but a mixture of anger and fear.

A stream of what looked like molten gold shot out of the Key, meeting the creature’s leap head-on. The thing squealed and hissed like a steam train coming to an emergency stop, twisted aside, and fell back to the street. It lay there, twitching and groaning, with smoke rising from a hole in its chest. But there were many more of its kind behind it, and, though they had slowed down after seeing the fate of their forerunner, Arthur knew they would get him if they all rushed him at once. He would take out as many as he could, he thought, and pointed the Key at the closest one.

‘Hey! Idiot! Up here!’

Something soft hit Arthur on the back of the head. He looked up. A small, grimy face looked down at him over the gutter of the roof, several stories up. Hanging beneath that face and a thin, ragged-clad arm was a rope made of knotted pieces of material. The end of it had just struck him.

‘Climb, stupid!’

Afterwards Arthur was never quite sure how he managed to put the Key through his belt, jump about eight feet off the ground, and climb most of the way up a four storey building all before the creatures could get halfway up the front steps.

‘Hurry! Faster! Nithlings can climb!’

Arthur glanced behind as he frantically pulled himself up, hands leaping to each knot with a speed that would have surprised any gym teacher. If only Mister Weightman could see me now, Arthur thought.

The creatures could climb. One of them was already on the rope, swarming up even faster than Arthur. Another one was swarming straight up the brick wall. It seemed to be able to stick its narrow fingers in the thinnest of gaps, but it was slower.

Arthur made it to the top and swung himself over. He saw a flash of steel and the rope went flying away, cut through at the top. A cry of pain indicated that the creature climbing it had fallen too.

‘Quick! Grab a piece of tile and throw!’

Arthur saw a pile of broken tiles, grabbed a jagged piece, and leaned over the gutter to let it fly. His rescuer was throwing too, with considerably greater accuracy. Arthur glanced at him . . . no . . . her, out of the corner of his eye as he took another shard and shot it down at the second climber.

He saw a girl about his own age, perhaps younger, though she was dressed as a boy, in the same old-fashioned clothes everyone else wore in this place. A crushed and battered top hat. A coat several sizes too large, mostly dark blue but patched with black. Knee-length breeches striped in several shades of grey, and very odd mismatched long socks or stockings that ended in one ankle-high and one shin-high boot. She had on several shirts of various sizes and colours and a mulberry-coloured waistcoat that looked, if not new, better kept than the rest of the ensemble.

‘Who are you?’ asked Arthur.

‘Suzy Turquoise Blue,’ replied the girl, throwing one last complete tile with satisfaction. ‘Got it!’

With a drawn-out scream, the climbing creature fell back to the street, landing on another one that had started up.

‘Come on! We’ve got to get out of here before the Commissionaires lumber into view!’

‘The who?’

‘Commissionaires! Hear the whistles? They’ll sort out the Nithlings and then they’ll want to arrest you for sure. Come on!’

‘Hold on!’ said Arthur. The whistles were much closer now. ‘Thanks for helping me and everything, but why shouldn’t I just talk to the . . . the Commissionaires? And who . . . what are Nithlings?’

‘You are an idiot, ain’t you?’ Suzy said, with a roll of her eyes. ‘There’s no time for quizzing.’

‘Why should I go with you?’ asked Arthur stubbornly. He didn’t move.

Suzy opened her mouth, but it was another voice that came out, clearly not her own. It was much deeper, and there was a rasp to it as well. It sounded a lot like Sneezer when he had fought with Mister Monday back at the oval, on that Monday that seemed so long ago.

‘The Will has found a way and you are part of the way. This is not the time for whims and obstinacy. Follow Suzy Blue.’

‘Right,’ said Arthur, shaken by the sudden deep voice coming from the girl. ‘Lead on.’

Suzy spun on her heel, coattails flying, and scampered up the roof. It was steep, but the tiles were rough and stepped, so it wasn’t too hard to climb. Arthur followed more slowly.

The ridge of the roof was flat, though only a foot wide. Suzy ran along it to a chimney stack, which she skirted around, hanging on to the chimney pot and leaning out in a way that made Arthur’s stomach do little flips. It was a long way to the ground.

He got to the chimney and started around it. Suzy was on the other side, looking down at an open balcony thrusting out of the next building. It was about ten feet away and six feet below them.

‘You’re joking! We’re not –’

Suzy jumped as Arthur spoke, landing perfectly on the balcony in a nimble crouch. She didn’t wait to see what Arthur did, but was up in a flash and working on the door, either picking the lock or forcing it open.

Arthur looked down. The street was very far away, and for a moment he was terribly afraid he’d fall. But that fear disappeared as he was distracted by what he saw. There was a full-scale battle in progress below. The whistles had stopped but were replaced by shouts and cries, howls and screams, yelling and a low rumble like constant thunder.

The creatures who’d appeared from the black vapour – the Nithlings – were bottled up in the middle of the street, completely surrounded by a well-disciplined band of large, burly men who wore shining top hats and blue coats, many of the coats adorned with gold sergeant’s stripes on their sleeves. They must be the Commissionaires, Arthur realised. The Sergeants were well over eight feet tall. The ordinary Commissionaires were shorter, around seven feet tall, and they were less fluid in their movements. The Sergeants used sabres that flickered with internal light, and the ordinary Commissionaires wielded wooden truncheons that flashed with tiny bolts of lightning and boomed with thunder as they struck their targets.

Not that the Nithlings were an easy mark. They bit and scratched and wrestled, and every now and then a Commissionaire would reel back through the ranks, blood streaming from his wounds. At least Arthur presumed it was blood. The Sergeants had bright blue blood, and the ordinary Commissionaires’ blood was silver, and it flowed like mercury, thick and slow.

‘Come on!’ shrieked Suzy.

Arthur tore his gaze away from the battle and focused on the balcony. He could do it, he knew. If it wasn’t such a long way to fall, he wouldn’t think twice about it. But it was a long way to fall . . .