‘DC Wolfe?’ she said. ‘I thought you would want to know.’ I heard her take a breath. ‘Tommy Defarge died at some point during the night.’

‘What?’

‘We will be conducting a full investigation, but the bottle we found in his room indicated that he had somehow obtained Fentanyl. He just slipped away. He wouldn’t have felt a thing.’

She was still talking about how difficult it is for patients to get their hands on prescription drugs at Summerdale and how there would have to be a full investigation but I was already running down the basement corridor screaming for the duty sergeant to unlock the holding cell containing Paul Warboys.

As he struggled with the keys I looked through the small window in the door and I saw the arterial spurt that had sprayed the cream-coloured tiles.

Then as the door to the holding cell swung open there was the body of Paul Warboys, a heavy flow of blood pulsing from the hole he had punched in his jugular and, still in his lifeless fist, the pen he had used to gouge, tear and finally open up the veins of his neck.

35

Chinatown is underground.

The world flocks to the restaurants, medical centres and massage parlours of Gerrard Street, Lisle Street and Shaftesbury Avenue, but there is another Chinatown below the city streets, in basements and cellars down a narrow flight of stairs, and it has existed since the city’s first Chinatown, Limehouse in the East End docks, was obliterated by the Luftwaffe.

It was down one of these unmarked flights of stairs, halfway down Gerrard Street, that I found Keith Li.

He was playing Mahjong in a low-ceilinged basement so huge that it must have stretched from Gerrard Street to Leicester Square. There were dozens of small square tables, each with four players, most of them elderly, every one of them Chinese, and the sound of their bone Mahjong tiles being banged together blurred into one unbroken cacophonous note.

Keith was playing with two old ladies and a man, none of them below eighty, yet they picked up and discarded tiles at breakneck speed, attempting to get three of a kind, four of a kind and running straight, but with a set of tiles that were three times the size of a pack of cards, depicting dragons, the four winds, bamboo, circles and a bewildering array of Chinese characters.

When the game ended and the tiles were face down and being shuffled – in Mahjong they call it washing – Keith stood up and looked at me for the first time.

‘Do you understand this game?’ he asked me.

‘I tried to once,’ I said. ‘But I’m not meant to understand it, am I?’