‘This Madam Theresa gave it to Ginger when she was fishing for girls to run. And clients. Maybe she doesn’t need either of them any more. Business sounds like it’s booming. What do you know about her, John?’

‘Back in the day, Madam Theresa Defarge ran the slickest sex operation in London. A-list clients. A-list girls. She took prostitution off the streets and put it into prime real estate at a time when everyone thought sex should be given away. She claimed there was no such thing as free love. They say she invented the term ‘call girl’. Discreet. Expensive. Exclusive enough for big names. A real beauty in her time. One of those Carnaby Street dolly birds, all black mascara and a skirt that was hardly there. She was supposed to have had a baby with one of her clients. But nobody ever saw the child. And that was all a long time ago. She dropped off the radar around the millennium. I thought the old girl would be pushing up daisies by now.’

‘Any pictures of her?’

‘I can goggle her for you,’ he said, peering into the screen of his elderly computer, glancing up to see me smiling. He had said it once as a genuine mistake – ‘I’ll goggle it, Max, shall I?’ – and now he said it whenever he wanted to lighten my mood.

There were two pictures of Theresa Defarge.

Both were taken in a photographer’s studio.

One showed a poster girl of London in the Sixties, a brunette, all panda-eye make-up and match-thin limbs, reclining on white satin sheets in a white baby doll nightdress. Her look was coquettish, inviting. She could have been a model for Mary Quant. The other photograph showed a woman in her late sixties, her hair that careful shade of white gold, wearing high black heels and a tight black basque against a pitch-black background, perched on what appeared to be a chair with a swathe of black silk thrown over the top. The look was challenging, defiant.

I could not tell that it was the same woman.

‘But why did she do the photo shoots?’ I said.

‘Some of these old-school madams always kidded themselves that they were in a branch of show business,’ John said. ‘I heard that some Hollywood producer promised to film her life story, no doubt when he was in his cups and with his trousers around his ankles. I guess it got stuck in – what do you call it? – development hell.’

I tried the number again, running through my lines.

But nobody answered.

I rang off and sipped my tea.

‘And what happens if you get in?’ John said.