Betty swallowed. ‘He’d lied to me about something, and I wanted to—’ She was about to say confront him, but checked herself. ‘Find out what he had to say.’ She looked at the policeman. ‘Ask John. It was he who told me.’

John sat on the edge of the sofa, his teacup still in his hand. He was staring at it, as if reading the leaves. The room was silent save for the hum of their breathing, the faint rumble of a train in the distance, the muffled tones of people coming and going in the hallway. The fire needed more coal, but she didn’t have the energy to shovel more on.

‘I’m sorry,’ she said. ‘I’m not being any use.’ She flapped her hand towards the window. She suspected Mrs H pulled the curtains to each night. There, that’s cosier, isn’t it?

‘Is there anyone who would wish your father dead?’

‘Do you think he was murdered?’ she said. What secret operations had he been caught up in, this little man in big man politics? John would know.

‘He committed suicide,’ she said before he could answer. That was obvious.

‘You seem sure,’ the detective said, but his voice hinted at a question. ‘Is there any reason why he would want to take his own life?’

She shook her head. ‘I can’t think of any.’ Had he felt remorse? ‘He swallowed cyanide, didn’t he?’

‘Only a post-mortem will tell us that,’ DS Fielding said. ‘What makes you think he took cyanide?’

‘I recognised the phial on the desk.’

‘Had you seen it before?’

She shook her head. ‘Not that one. Not since we came to England.’

The detective flicked through some notes, took a glance at John. ‘In 1945,’ he said, looking up at her as if for confirmation. ‘From Germany.’

It was supposed to be a secret, she thought. We will not talk of it. But the detective was aware of it, about her father. Highest security. Of course. Everyone knew about her father. She was the only one who didn’t.

‘Did you know your father had it?’

Betty shook her head. ‘I had no idea,’ she said.

‘But you recognised it.’