We are finally alone.

‘How did you find me, Herta?’ Vati asks as soon as the front door is shut. ‘How did you know?’ He sinks onto the sofa and presses two fingers between his eyes. ‘Is this what you were looking for in my study?’

I remain standing, fighting the urge to physically hurt him. To assuage the rage creeping through my veins at the thought of how this happy little domestic set-up with Hilda and Sophie would hurt poor Mutti if she were here now.

‘I’ve known about this for a long time,’ I tell him. ‘I saw you once with Fräulein Müller and the little girl, Sophie. I saw… well, I just knew.’

‘Poor Herta.’ He peers up at me. ‘That wasn’t the best way to find out. I always intended to tell you – and Karl, of course – eventually. When the time was right. I want you to have a relationship with your half-sister. And Hilda is expecting again. Nothing will replace Karl, but it will be good for you to have more siblings.’

Karl is dead and Hilda is expecting again. You think that is good for me?

I fold my arms across my chest, keep my distance. Keep the fire inside in check.

‘Come,’ he says, his voice weary. ‘Sit down.’ He pats the cushion next to him.

I stay where I am.

‘I need you to do something, Vati. For me.’ My voice is tight. ‘Many arrests were made last night. Of Jewish people.’

‘What of it?’

‘Some friends of mine were arrested,’ I say with a pounding heart. ‘I want you to help them. Walter Keller. Karl’s friend from… before, and his father and uncle are being transferred to Buchenwald. I want you to get them out.’

Vati stares at me.

‘How on earth do you know…?’ His voice tails off. I can almost see his brain computing behind his eyes. ‘And just why would you want me to do that?’ he asks, his tone acid.

‘Because he used to be Karl’s friend. But mostly because he saved me, that time, from drowning. One good deed deserves another.’ Finally, I smile at him.

Vati sits up straighter. Shuffles round to face me. He opens his mouth, closes it. Shakes his head. He seems to be struggling to put thoughts into words.

‘I tolerated that boy hanging around our house far too long… Hélène was too soft…’ He looks at me. His face changes; a shadow of something. ‘What does that boy mean to you?’ His voice is low with warning. ‘Karl tried to warn me. Now I understand.’ He seems to drift off. Shifts his gaze towards the window. He snaps it back to me. ‘Ingrid. She told me she’d made an allegation to the Gestapo. But then she withdrew it the next day. Said she was too afraid…Was that about you, and that boy?’

You sly snake, Ingrid.

‘There was nothing between us,’ I say firmly, ‘Karl, Ingrid, they got it wrong. But I bumped into him a few times, yes. And I went to tell him about Karl—’