It was Scuff who spoke to them, leaving the River Police in shadows with their lanterns half concealed.

Then they moved on again, probing the darkness with their feeble lights. The thought made Monk's stomach churn and his throat tighten: What would happen if they dropped the lamps? They would never get out of here. One day, in a week, or a month, some tosher would find their bones, picked clean by rats.

The last tosher they had questioned, half a mile back, had said there were people using this old way to get from one part of the city to another. The man they were looking for, whose name no one spoke, was one of them. In the subterranean world there seemed little of either friendship or enmity; it was simply coexistence, with rules of survival. Those who broke them died.

It seemed an age before Scuff finally led them up a ladder. Their feet clanged on the iron rungs. A few yards later they passed a sluice rushing so loudly they could not hear their own voices. Above, in a dry passage leading to a blind end, a group of men and women were sitting beside a fire, the smoke going up through a hole a little distance away and disappearing into utter darkness.

A short whispered conversation followed between Scuff and an old woman.

"Which way, ma?" Scuff asked her, touching his tooth to remind her whom he was referring to.

She shivered and jerked her head to the left. A younger man argued with her, pointing to the right. Finally Orme agreed to follow the youth one way with Kelly and Jones and return if he found nothing. Monk took the other two men and went with Scuff the way the old woman had indicated.

Half an hour later, after more twists and climbs, they emerged into an open cutting, air fresh and cold on their faces.

"She lied," Scuff said bitterly. "Scared, I spect. Daft of-" He stopped short of using the word he had been going to say. "That way." He pointed back where they had come from. At the next branch in the tunnel they divided again, Monk and Scuff going alone down more iron steps and deeper into the bowels of the earth.