Platform 373 was a clinical tube. A featureless cylinder of white curved around a narrow platform and a single track, each end disappearing into dark tunnels leading deeper into the bowels of the Underground. A single strobe-light lit the station from above. There were no posters, no benches, no graffiti; after all, defacing government property amounted to anarchy and a fine of three-weeks-wages – a public flogging was a ‘best-case’ punishment.

There was nothing but solid white concrete, save for a small concave square, ten-inches-by-ten, dead centre in the wall and facing out onto the platform. It looked to Hari like a mirror, and when he peered in his distorted face reflected, features bent into a grimace. Insidious, he’d heard that word once, the face was insidious. Beneath the square, a rectangular plaque stated: Platform 373: Property of The Government.

‘Keep close,’ said Pa, placing a hand on Hari’s shoulder, turning him back towards the track. A grumbling, like the rumble of a huge beast’s stomach, reverberated from one of the tunnels. ‘Ere it comes.’

Hari looked along the platform. There was a handful of passengers, not many this time of night. They worked in the same district as he and Pa. Their faces all looked alike, leathery and tanned, though it could be dirt from the machinery. The grumbling noise built, then hurtled from the tunnel, a long carriage like a headless metal snake. No headlights. No windows. Regular doors. And with it came a rancid pong like burnt meat. Pungent. Ma had once said that word, long ago when language was colourful, when ...