They stood like exhausted combatants. Each waited for the other to move.

“So what now?” said Lemuel. His voice was surly.

“We go to Griss Twist tomorrow night,” said Isaac. “The construct promised help. We can’t risk not going. I’ll meet you both there.”

“Where are you going?” said Derkhan in surprise.

“I have to find Lin,” said Isaac. “They’ll be coming for her.”

Chapter Thirty-Six

It was almost midnight. Skullday was becoming Shunday. The moon was one night off full.

Outside Lin’s tower, in Aspic Hole itself, the few passers-by were irritable and nervous. Market day had passed, and its bonhomie with it. The square was haunted by the skeletons of stalls, thin wooden frames stripped of canvas. The rubbish from the market was piled in rotting heaps, waiting for the dustcrews to transport it to the dumps. The bloated moon bleached Aspic Hole like some corrosive liquid. It looked ominous, shabby and mean.

Isaac climbed the stairs of the tower warily. He had had no way of getting a message to Lin and he had not seen her for days. He had washed as best he could in water niched from a pump in Flyside, but he still stank.

He had sat in the sewers for hours the previous day. Lemuel had not allowed them to leave for a long time, decreeing that it was too dangerous during the light.

“We have to stick together,” he demanded, “until we know what we’re doing. And we are not the most unobtrusive bunch.” So the four of them had sat in a room awash in faecal water, eating and trying not to vomit, bickering and failing to make plans. They had argued vehemently about whether or not Isaac should see Lin on his own. He was absolute in his insistence that he be unaccompanied. Derkhan and Lemuel denounced his stupidity, and even Yagharek’s silence had seemed briefly accusatory. But Isaac was quite adamant.

Eventually, when the temperature fell and they had all forgotten the stink, they had moved. It had been a long, arduous journey through New Crobuzon’s vaulted conduits. Lemuel had led, flintlocks ready. Isaac, Derkhan and Yagharek had to carry the construct, which could not move in the liquid filth. It was heavy and slippery, and it had been dropped and banged and damaged, as had they, falling into the muck and swearing, slamming hands and fingers against the concrete walls. Isaac would not let them leave it.

They had moved carefully. They were intruders in the sewer’s hidden and hermetic ecosystem. They had been keen to avoid the natives. Eventually they had emerged behind Saltpetre Station, blinking and dripping in the waning light.

They had bedded down in a little deserted hut beside the railway in Griss Fell. It was an audacious hideout. Just before the Sud Line crossed the Tar by Cockscomb Bridge, a collapsed building made a huge slope of half-crushed brick and concrete splinters that seemed to shore up the raised railway. At the top, dramatically silhouetted, they saw the wooden shack.

Its purpose was unclear: it had obviously remained untouched for years. The four of them had crawled exhausted up the industrial scree, shoving the construct before them, through the ripped-up wire that was supposed to protect the railway from intruders. In the minutes between trains, they had hauled themselves along the little fringe of scrubby grass that surrounded the tracks, and pushed open the door into the hut’s dusty darkness.

There, finally, they had relaxed.

The wood of the shed was warped, its slats ill-fitting and interspersed with sky. They had watched out of the glassless windows as trains burst by them in both directions. Below them to the north, the Tar twisted in the tight S that contained Petty Coil and Griss Twist. The sky had darkened to a grubby blue-black. They could see illuminated pleasure-boats on the river. The massive industrial pillar of Parliament loomed a little way to the east, looking down on them and on the city. A little downriver from Strack Island, the chymical lights of the old city watergates hissed and sputtered and reflected their greasy yellow glow in the dark water. Two miles to the north-east, just visible behind Parliament, were the Ribs, those antique sallow bones.

From the other side of the cabin they saw the spectacularly darkening sky, made even more astonishing by a day in the reeking dun below New Crobuzon. The sun was gone, but only just. The sky was bisected by the skyrail that threaded through Flyside militia tower. The city was a layered silhouette, an intricate fading chimneyscape, slate roofs bracing each other obliquely below the plaited towers of churches to obscure gods, the huge priapic vents of factories spewing dirty smoke and burning off excess energy, monolithic towerblocks like vast concrete gravestones, the rough down of parkland.

They had rested, cleaned the nightsoil from their clothes as much as they could. Here, finally, Isaac had tended the stub of Derkhan’s ear. It had numbed, but was still painful. She bore it with heavy reserve. Isaac and Lemuel had fingered their own scarred remnants uncomfortably.

As the night had crept up faster, Isaac had readied himself to go. The argument had erupted again. Isaac was resolute. He needed to see Lin alone.

He had to tell her that she was in danger as soon as the militia connected her to him. He had to tell her that her life as she had lived it was over, and that it was his fault. He needed to ask her to come with him, to run with him. He needed her forgiveness and her affection.

One night with her, alone. That was all.

Lemuel would not acquiesce. “It’s our fucking heads too, ‘Zaac,” he had hissed. “Every militiaman in the city is after your hide. Your helio’s probably pasted up in every tower and strut and floor of the Spike. You don’t know how to get around. Me, I’ve been wanted all my working life. If you go for your ladybird, I come.”

Isaac had had to give in.

At half past ten, the four companions had wrapped themselves in their ruined clothes, obscuring their faces. After much coaxing, Isaac had finally been able to goad the construct into communication. Reluctantly and torturously slowly, it had scratched out its message.

Griss Twist Dump number 2, it had written. Tomorrow night 10. Leave me below arches now.

With the darkness, they had realized, came the nightmares.

Even though they did not sleep. The mental nausea, as the slake-moth dung polluted the city’s sleep. Each of them grew tetchy and nervous.

Isaac had stashed his carpet bag, containing the components of his crisis engine, under a pile of wooden slats in the shack. Then they had descended, carrying the construct for the last time. Isaac hid it in an alcove created where the structure of the railway bridge had crumbled.

“Are you going to be all right?” he asked it tentatively, still feeling absurd talking to a machine. The construct did not answer him, and eventually he had left it. “See you tomorrow,” he said as he left.

The criminal foursome skulked and stalked their clandestine way through New Crobuzon’s burgeoning night. Lemuel had taken his companions into the alternative city of hidden byways and strange cartography. They had evaded streets wherever there were alleys and alleys wherever there were broken channels in the concrete. They had crept through deserted yards and over flat roofs, waking the vagrants who grumbled and huddled together in their wake.

Lemuel was confident. He swung his primed and loaded pistol easily as he climbed and ran, keeping them covered. Yagharek had adapted to his body without the weight of wings. His hollow bones and tight muscles moved efficiently. He swung lithely over the architectural landscape, leaping obstacles in the slate. Derkhan was dogged. She would not let herself fail to keep up.

Isaac was the only one whose suffering showed. He wheezed and coughed and retched. He hauled his excess flesh along the thieves’ trails, breaking slates with his heavy slapping footfall, cradling his belly miserably. He swore constantly, every time he exhaled.