‘Well,’ answered the tough with the shaven head, ‘I don’t mind about that. It’s him we’re after, not you.’

‘You’ll have to fight me first,’ said Henry gallantly.

‘I don’t mind about that,’ the tough told him.

Without warning, the other bruiser, with spiky hair and a tight-fitting tailcoat, stepped forward and punched Henry very hard in the face. Collis, in a split second, saw Henry rolling across the street in a flurry of evening dress and horse manure, and then something as fast and heavy as a cantering pony collided with his shoulder and sent him hurtling against the iron railings. He bounced off, as if he were made of India rubber, but his back was bruised and he hit his ear on the sidewalk. He tried to get up, but a huge boot kicked him in the hip, and he felt as if the night was bursting in every direction.

He heard Henry yelling a hoarse drunken yell, and he lifted his head. The tough in the tailcoat had Henry’s neck in an armlock and was screwing his knuckles into the side of his temples. Collis tried to pull himself to his feet, and had almost succeeded when a fist as hard as a doorknob punched him in the ear and he pitched over again.

From somewhere, Henry’s voice shouted, ‘Collis! On your feet! Run!’ and somehow he managed to grasp the railings and pull himself upright again, with bright pinpoints of light sparkling in front of his eyes.

The shaven-headed tough called, ‘More? You want more?’ and charged at him again, his fists revolving like a funfair ride. But then Collis, his left shoe uncomfortably squashed down at the back, his pants torn at the seams, his silk hat crushed over one eye, was up and running. Henry was already halfway down Spring Street, his legs pumping up and down as if he were dancing a very fast polka.

The bruisers came hard behind them, silent and dogged. Collis only once glanced over his shoulder, as they ran across Lafayette Street, dodging between the carriages, and the two toughs were almost close enough to sink their broken teeth into his ear.

‘Collis! Follow me!’ Henry shouted, and unexpectedly turned down a narrow, pitch-black alley between two dilapidated red-brick houses. Collis ran after him blindly, holding his hands out in front of him in case he struck a wall or a fence in the dark. The alley reeked of damp and sewage, and echoed with the splank-splank-splank of running feet.