Her face froze. She turned to him, twisting in slow motion, searching his eyes for an answer. She fumbled her lip with her teeth, rubbed her hand along her cheek. ‘Chinese ceramics,’ she said. ‘Let’s look at those.’ Betty pushed up from the bench and stepped forward. She was unsteady and he walked behind her, arms at the ready, to catch her, in case she fell.

‘More cabinets,’ she said as they entered the gallery. ‘More dreary cabinets.’ She walked into the centre of the gallery. ‘Plates and pitchers and cups and ewers.’ She stared, pointing. ‘Though that is very beautiful. Ming. I like it.’ She pressed her nose against the glass, her voice muffled as she spoke.

‘You seem to know a lot about my father,’ she said. ‘Have the Soviets told you this?’ She pulled away and faced him. ‘If you’re working for the Soviets, why don’t you just feed me to the wolves?’

‘Because I love you,’ he said.

She bit her lip, turned away again. ‘Before,’ she said, bending down to study a teacup at the bottom of the cabinet, ‘you said they blackmailed you, in Berlin, but you wouldn’t tell me if you’d given them secrets.’ She stood up, level with him. ‘Why are they blackmailing you now?’

He looked away, the fine ceramics merging into one blue and white porcelain blur.

‘You fed the Russians what they wanted, didn’t you? This was my sister they used. Murdered. You didn’t give a damn, did you? Too busy saving your own skin.’ Her voice had risen, and though the gallery was empty, he put a finger on his lips and a hand on her shoulder.

‘No,’ he said. ‘I told my commanding officer. Came clean with him. Betty…’ He blew through his mouth, lips vibrating. ‘I was used as a double agent, feeding the Soviets misinformation.’

She narrowed her eyes, her mouth open, her head turned to one side. ‘Why can they still blackmail you?’

‘I also fed them real information. Just once. Something specific. Something not important, but by then they knew I had been double-crossing them. The British didn’t know what I’d done but they knew I was in danger, so moved me to Nuremberg.’

She was taking it in, working through the levels of trickery and duplicity.

‘And are you still a double agent?’

He nodded. ‘I was. A quid pro quo,’ he said. ‘The government won’t prosecute me for that one lapse if I monitor you.’

‘Me?’

‘As they see it, you’re a weak link, a security risk, because of your political leanings.’

‘My political leanings? What on earth do they mean?’

‘CND and all that.’

‘Good God, I thought this was a democracy. Why would I be a threat?’

‘For the same reason the Russians see you as an asset. You could turn him.’