Throwing open the window, I manoeuvre myself onto the sill. From here I can easily reach out and touch the tips of the branches of the tree, but they bow easily under the lightest pressure. There is no way they will take my weight. I cry out and slam the window shut in frustration. Pacing the room, I rub away my useless tears with balled fists.

‘Fraülein Herta?’ Bertha’s voice, outside the door, accompanied by a soft knock. ‘What is it?’ She opens the door a crack. ‘May I—’

‘Oh Bertha!’ I fly to the door and pull her inside. ‘It’s the most terrible thing!’ I whisper, embracing her as though she were my mother. She freezes in shock, arms locked at her side. Then slowly, gently, she layers her arms around my back, patting between my shoulders as she might a small child.

‘There, there,’ she says soothingly. She is warm, her body solid against my own. I let myself melt into the comfort of her.

After a few moments, she gently takes my shoulders and holds me away. ‘Whatever has happened?’ she asks, studying my face.

Watching the door and speaking in a hoarse whisper I quickly tell her that Mutti caught me in Vati’s study. I give her the briefest outline of what I read in that shocking command from Herr Himmler, tell her that I’m desperate to leave the house and warn Walter and his family of what is going to happen.

Bertha shakes her head and bites her lip. ‘You can’t do anything, Fraülein,’ she says after a pause. ‘This is too dangerous to involve yourself in. You must obey your parents, Herta. There are some things which are too big, too much to take on alone.’

She’s right. It is too big. But if I can do this one minuscule thing which might help at least Walter’s family, then I must do it. He would do it for me, I know it.

My tears have dried and I’m calm.

‘I’ve a plan, Bertha,’ I say slowly, looking deep into her troubled eyes. ‘I just need two tiny favours. Please, will you help me?’

I scribble a note.

My dear Erna,

That matter we spoke of yesterday is much, much bigger than we thought. People must be warned that terrible things are going to happen tonight. They must not fight back. I hope your father can do something. It’s all I can say for the moment. I hope you understand.

Yours,

Herta.

Bertha promises to have it delivered, and reluctantly agrees to my second request.

*

When Vati comes home I’m allowed downstairs to learn my punishment. Sitting in his study, he pours himself a whisky and drinks it down in a few gulps. I watch as he pours another.

‘I truly don’t know what’s happened to you, Herta. Upsetting your mother. Defying me. I’m giving you one chance. What is going on?’

‘Nothing is going on, Vati.’ I meet his pale eyes and he moves his gaze. He’s agitated, nervy. He walks around the room. ‘I’m sorry I looked at your papers. It was wrong of me, but Mutti told me something big was going to happen. Nobody ever tells me anything properly. I decided to find out for myself.’