‘There’s no reason why you would. Long firm fraud is when a company is set up for fraudulent purposes. An apparently legitimate business establishes a good credit record and then, out of the blue, everyone gets stiffed. Goods are bought on a massive scale with no intention of ever paying for them.’

‘But what’s the point in that?’

I could not help but smile at his innocence.

‘The goods get sold elsewhere, Mr Warboys. It’s how the criminal mind works. It’s a scam that was perfected in the Sixties. The big family mobs loved the long firm. Reggie and Ronnie Kray. Charlie and Eddie Richardson.’

He looked at me.

‘And Paul and Danny Warboys,’ I said. ‘A long firm takes time and money to set up but it can be massively profitable. It ends with the business run into the ground and the owners long gone. Sometimes they burn the place to the ground before they do a bunk.’ I watched his face carefully. ‘Do you think your father burned that place down?’

He shook his head.

‘No,’ he said. ‘Because my father would never do anything to hurt my son.’ And then a look of doubt came over his face. ‘At least, not deliberately.’

‘I’ve seen your father’s new home. It’s an apartment in a luxury block by the river. It’s not big, but he doesn’t look as if he’s struggling to get by on his state pension.’

Barry Warboys laughed bitterly.

‘My father is broke, Detective. The last of the money was in that Essex house. My father couldn’t sell it while my mother was alive. It was in her name – it had been in her name for forty years, ever since he went away for his life sentence, ever since it seemed the authorities might seize it. But as soon as my mother was gone, there was nothing to stop him putting it on the market.’

I thought of Paul Warboys alone in the soulless luxury of his riverside apartment block and I remembered something my grandmother used to say. Fur coat and no knickers. Meaning a public show of luxury and a private reality of poverty. Was that what the old gangster had come to?

‘Why are you telling me this?’ I said.

‘You asked me about my father’s finances,’ he said. ‘And now I’m telling you. I don’t believe he burned down the Champagne Room. I don’t believe that he – or Stephen – had anything to do with those women in Chinatown. But I do not want to keep anything from you. This is not easy for me, Detective.’

‘I appreciate that,’ I said. ‘If he needed one last score, what do you think your father would do?’

His voice was soft as a prayer and I could hardly hear him over the slap of leather hitting flesh and bone and the groans of pain coming from the ring.