Spit Hearth, to the south-east, was bisected from above by the skyrail connecting the militia tower at the point of Brock Marsh to Perdido Street Station. It was part of the same boisterous zone as Sheck, a wedge of smaller shops and houses made of stone and patched with brick. Spit Hearth had a twilight industry: Remaking. Where the borough met the river, subterranean punishment factories emitted wails of pain, sometimes, and hastily smothered screams. But for the sake of its public face, Spit Hearth was able to ignore that hidden economy with only a slight show of distaste.

It was a busy place. Pilgrims made their way through it to the Palgolak temple at the northern edge of Brock Marsh. For centuries, Spit Hearth had been a haven for dissenting churches and religious societies. Its walls were held together with the paste from a thousand mouldering posters advertising theological debates and discussions. The monks and nuns of peculiar contemplative sects walked the streets hurriedly, avoiding eye contact. Dervishes and hieronomers argued on corners.

Wedged gaudily between Spit Hearth and The Crow was the city’s worst-kept secret. A grubby, guilty stain. It was a little region, in the city’s terms. A few streets where the ancient houses were narrow and close, could easily be joined by walkways and ladders. Where the constricted slivers of pavement between tall and strangely adorned buildings could be a protective maze.

The brothel quarter. The red-light zone.

It was late in the evening as David Serachin walked through the northern reaches of Spit Hearth. He might have been walking home to Skulkford, due west under the Sud Line and the skyrails, through Sheck, past the massive militia tower to Skulkford Green. It was a long but not implausible walk.

But when David passed under the arches of Spit Bazaar Station, he took advantage of the darkness to turn and gaze back the way he had come. The people behind him were only passers-by. He was not followed. He hesitated a moment, then emerged from beneath the railway lines, as a train whistled above and sent booms reverberating around the brick caverns.

David turned north, following the path of the railway line, into the outer reaches of the whoretown.

He dug his hands deep into his pockets and thrust his head down. This was his shame. He simmered in self-disgust.