I can feel Erna’s fierce gaze at my profile. ‘So, why are you telling me this, now?’

‘Someone has reported us. It could have been our maid, who might have seen me with him. She watches me, Erna, and I have to be so careful. Anyway, the Gestapo want him for Rassenschande. He has a visa to go to England, but only if he marries a girl there.’

‘Jesus.’

‘But,’ I rush on, ‘he can’t leave Germany without a passport and his exit tax paid. I need to help him. And I need an ally.’

She shakes her head. ‘This is a lot to take in.’

We stop by the church, near the spot where I declared myself to Walter so long ago.

At last I dare to take a look at Erna’s face. Her eyes are wide, her skin pale with shock.

‘Well, what do you think of me now?’ I ask, looking into those deep green pools, where her soul, pure and clean, meets, perhaps in her eyes, my filthy, tarnished one.

For a few ticks she says nothing. ‘I can hardly believe it,’ she says at last.

‘You promised you wouldn’t tell…’

‘No! Hetty, never!’ She grabs both of my hands. ‘I love you, you silly old thing. I love you more for this. More than ever!’

An exhaustion engulfs me. I feel so tired, my limbs leaden, as if letting out this secret has finally released me to feel the weight of it.

‘You see, Hett,’ Erna drops her gaze, ‘I have a confession of my own.’

‘What?’

‘I should have confessed before. My father is no blithering old fool. He can be, of course, but he’s much more than that. He’s a vehement, secret, anti-Nazi. He loathes Hitler and all he stands for. We all do.’ She looks around the nearly empty square, dropping her voice to a whisper. ‘There is a small network of us in Leipzig. Just a handful. Not enough to make any difference. Everyone is too afraid.’

I shake my head, trying to clear it, keep it thinking straight about the implications of all of this.

‘It’s why my father wanted me in the BDM. Encouraged me to do well, to avoid suspicion. He’s convinced the Gestapo are watching.’

‘But what about Karl? Why did you walk out with him?’

‘That’s the other part of my confession. I liked Karl, of course. He was hard not to like, so handsome and sweet. But I didn’t love him, not the way he loved me. He was so good to me and I feel ashamed – but I was worried about my father. He can be… indiscreet. I was afraid for him, and I thought that if I was with Karl, it might protect him. Keep suspicion away…’

The ground shifts; the world twists and turns.

Is there anyone who is truly as they appear?

‘Being close to Karl and your family has helped,’ Erna goes on, but her words spin around my head unheard. She has used us. Both of us, Karl and me, for her own ends. I don’t mean anymore to her than that, never have. I always found it hard to understand why anyone as charming, sophisticated, accomplished as her, would want to be my friend.