She had loomed in my imagination as some kind of giant. The two photographs I had seen of her, taken fifty years apart, had given the impression of broad shoulders and endless legs, a woman who had successfully carved a career from the desires of men. But as I felt her fingers dig into my arm, guiding me inside, I saw she was barely five feet tall.

Her face, once as beautiful as any face in London, was withered by the years but she beamed up at me with a smile so porcelain white it would have looked out of place on a twenty-year-old.

She led me into what felt like a Victorian drawing room, so strict was the segregation of men and women, so rigid was the old-world formality fifty floors above the city. A line of young women sat along one wall, talking quietly among themselves and waiting to be approached. Edie Wren was not among them, a fact that I noted with a mixture of relief and dread.

There was a small bar in one corner of the room, served by a bartender with a shaven head and a bow tie, and a handful of men in suits with no ties stood around, quietly conversing in their own language as they clutched their drinks and measured the women. Beyond the windows and far below, London glittered like a box of jewels emptied by some careless god.

‘Sit with me,’ Madam Theresa said. She took my hand. ‘How’s our mutual friend?’

‘Ginger’s very well.’

‘Your first visit to us,’ she said, and called a waiter with a slight turn of her head.

He held a tray with a silver bowl.

‘Adam will take your drinks order and – if you don’t mind – your telephone. We charge it for you while you’re here. And of course the absence of phones ensures the total privacy of other guests.’

Her voice lilted with a French or Belgian accent, but deep beneath it I felt I could detect the eternal, undying vowels of a council estate in a small town somewhere in the north of England.

I placed my phone in the silver bowl, my face impassive.

The waiter took it away.

Now I saw that the main room led to a corridor with a line of other rooms. A door opened and a man emerged with a tall black woman walking two places behind him. I recognised him as a senior politician. He did not look our way as he left the penthouse with the woman walking behind him. The waiter brought my water.

‘Mr Dempsey,’ Madam Theresa said, more businesslike now. ‘May I explain how our establishment works?’

I nodded.

And I tried not to stare as Edie Wren came out of one of the rooms. Rabia Demir was with her.

She appeared to have trouble standing. Edie seemed to be supporting her.

Edie nodded briefly without looking at me.

Now, she was saying.

Tell them now.