Craig stood there in the darkness without moving until the Cooper had driven away and then he unlocked the door of the Jaguar and climbed behind the driving wheel. He knew something was wrong the moment she refused to start. He tried several times ineffectually, then took a flashlight from the glove compartment, got out and raised the bonnet. The rotor arm had been removed, an obvious precaution in case he’d beaten them into the car. He sighed heavily, dropped the bonnet and moved across to the main gates.

It was only twenty past eleven and there were plenty of late buses about, but in any case, he would be able to get a taxi in City Square. He crossed the road quickly, head down against the driving rain.

Someone moved out of a doorway behind him, he was aware of that, and then the pain as a sharp point sliced through his raincoat and jacket to touch bare flesh.

‘Keep walking,’ Billy Stratton said calmly. ‘Just keep walking or I’ll shove this right through your kidneys.’

They turned into a narrow alley a few yards further along, Craig walking at the same even pace, hands thrust deep into his pockets. A lamp was bracketed to the wall at the far end and beyond, the river roared over a weir, drowning every other sound.

‘A good thing I came along, wasn’t it?’ Stratton said. ‘But then I have an instinct for these things. I knew something would go wrong just as I knew you were trouble from the first moment I clapped eyes on you. But not any more, you bastard. Not any more.’

Craig took to his heels and ran and Stratton cried out in fury and went after him. The cobbles at the end of the alley were black and shiny in the light of the old gas lamp and beyond the low wall that blocked the end, the river rushed through the darkness.

As Craig turned, Stratton paused, the knife held ready, a terrible grin splitting the white face, and then he moved with incredible speed, the blade streaking up. To Duncan Craig, it might have been a branch swaying in the breeze. He pivoted cleanly to one side, secured the wrist in a terrible aikido grip and twisted the hand back in the one way nature had never intended it should go, snapping the wrist instantly.

Stratton screamed soundlessly, his agony drowned by the roaring of the river. He staggered back clutching his broken wrist, mouthing obscenities, and as Craig picked up the knife and moved towards him, turned and stumbled away.

Craig went after him, but Stratton thundered along the alley as if all the devils in hell were at his heels, emerged into the main road and ran headlong into the path of a late-night bus.