I began to form a word, a cry to beg for help, but, as I lifted my chest to draw in breath, Charles seemed to harden his thoughts and crushed his weight back down on to me, so that I could hardly suck in enough air to breathe. I could only croak out a cry for help so weak that it wouldn’t have been heard outside the room.

The door knocker clacked again. The man was still there. I struggled, trying to turn on to my side, but Charles pulled my head back hard by my hair.

‘Let me go,’ I gasped. ‘Let me go.’

The letterbox creaked open. ‘Is anybody at home?’ Looking in, whoever it was would see only an empty hallway. The letterbox closed again with a dull flapping sound, and we waited, listening, but there was only silence. We stayed there for a long time, long enough for the caller to leave and be swallowed up by the smog. I felt the hope that I had built slipping out of me.

Charles pushed himself away. I no longer had the breath and blood to get up and run. He sat on the bed, shaking still with his own shock and nerves. ‘Sit there,’ he said, pointing to the dresser.

I dragged myself to the dresser in the room I had shared with Nick, the room where we had first made love after our wedding, looking at my cosmetics, at the compact and the rouge. Lorelei’s voice came through the wall, speaking over a soaring violin. Charles sat staring at the floor. He couldn’t let me go. I knew it. He knew it. If he did, he would get the rope. He was as trapped as I was.

And, even as we sat there, both of us unable to leave that room, each looking for a way out that couldn’t possibly exist, I couldn’t help but think the same thought that I had had on the balcony with Ian Fellowman: that this was the squalid natural ending to those dreams he and Anthony Blunt and Kim Philby and Guy Burgess and Arthur Wynn and John Cairncross had woven for us. This was where they ended: in ordinary people desperate to run away, but too fearful of the consequences that waited outside like bare-toothed dogs. All the words these men had poured into our ears and down our throats night and day – all they really amounted to when the light hit them was this havoc. This utter wreckage.

Something fell away in me then, leaving a numbness of feeling. It was like half my being had gone, leaving only my body. I didn’t care any more. Not for any of it. There was nothing left to care. ‘Charles,’ I said quietly. ‘I’m going. Please don’t stop me. Just let me go.’