But she would not see it.

She had already spoken to Cornfed, asking him to vouch that she had been there, should Isaac ask (she could not foresee that he would, but she might as well be safe). Cornfed had been delighted, flicking his white hair out of his face and flamboyantly begging eternal damnation for himself should he breathe a word. He clearly thought she was two-timing Isaac, and considered it a privilege to be part of this new twist to her already scandalous sex life.

Lin could not make it to his show. She had business elsewhere.

The cab was progressing towards the river. She swayed as the wooden wheels hit more cobblestones. They had turned onto Shadrach Street. The market was to their south now: they were above the point where the vegetables and shellfish and overripe fruit petered out.

Swelling fatly above the low houses before her was the Flyside militia tower. A vast, filthy, pudgy pillar, squat and mean, somehow, for all its thirty-five storeys. Thin windows like arrow-slits peppered its sides, their dark glass matt, immune to reflection. The tower’s concrete skin was mottled and flaking. Three miles to the north Lin caught a glimpse of an even taller structure: the militia’s hub, the Spike, that punctured the earth like a concrete thorn in the heart of the city.

Lin craned her neck. Oozing obscenely over the top of the Flyside tower was a half-inflated dirigible. It flapped and lolled and swelled like a dying fish. She could feel its engine humming, even through the layers of air, as it strained to disappear into the gun-grey clouds.

There was another murmur, a buzzing dissonant with the airship’s drone. Somewhere nearby a support strut vibrated, and a militia-pod streaked northwards towards the tower at breakneck speed.

It careered along way, way above, suspended from the skyrail that stretched out on either side of the tower, threaded through its summit like wire through some colossal needle, disappearing to the north and the south. The pod slammed to a sudden stop against the buffers. Figures emerged, but the cab passed on before Lin could see any more.

For the second time that day Lin luxuriated in the taste of cactus-people sap, as the pterabird loped towards the Greenhouse in Riverskin. Shut out of that monastic sanctuary (the twisting, intricate panes of its steep glass dome looming to the east, in the heart of the quarter), despised by their elders, small gangs of cactus youth leaned against shuttered buildings and cheap posters. They played with knives. Their spines were cropped in violent patterns, their spring-green skin savaged with bizarre scarification.

They eyed the cab without interest.

Shadrach Street dipped suddenly. The cab was poised on a high point, where the streets curved sharply down away from it. Lin and her driver had a clear view of the grey, snow-specked jags of mountains rising splendidly to the west of the city.

Before the cab trickled the River Tar.

Faint cries and industrial drones sounded from dark windows set into its brick banks, some of them below the high-water mark. Prisons and torture-chambers and workshops, and their bastard hybrids, the punishment factories, where the condemned were Remade. Boats coughed and retched their way along the black water.