I cannot help but feel that the essence of me is slowly being sucked out.

We gather our towels and hurry down the rocky slope, following the sound of rushing water.

Doing the right thing means personal sacrifice. Give up what you want, for the good of all.

I shake my head, try to clear it. Still He lives inside my skull, the Führer who sees everything – my deepest fears, my hopes and dreams. And some of the thoughts I’ve had since that Sunday, I really don’t want him to know.

‘Look around you, Hetty. We are truly on top of the world,’ Erna says.

All around us are hazy mountains and deep green valleys. The glassy black curve of a lake lies in a basin, thousands of feet below. Above, craggy rocks jut skywards and thin strips of white cloud float lazily in a clear blue sky.

This is the land of the gods. There is something cleansing in the scenery.

‘It’s sublime,’ I admit.

‘Now let’s swim,’ she says, and I watch her as she walks towards the pool, her auburn plaits flickering gold, her back long and shoulders strong. She is the sun, a beautiful, golden orb drawing everyone towards her. I’m in her shadow, a little planet sucked into her orbit, resentful of her power. And yet, I can’t help but love her – her purity and honesty, her positivity.

She is so much better than me.

I wish I could tell her about Walter. Ask her advice. Just four more days until we are due to meet on the bridge.

‘… A dastardly Jew caught with a beautiful young German woman…’ I can see his mouth form the words. His lips pursing, eyes taking me in.

I cannot tell her – or anyone. I promised not to. But it’s so hard. Boys only ever notice Erna, never me. And Walter isn’t just any boy. He has good looks. He is brave, manly. He could be the epitome of the Aryan ideal. It would be so easy to forget what he really is.

I pretend he isn’t a Jew and imagine us together; figures lit up as if in a movie. There’s an intense look in his eye, then his lips are on mine. He says to me, ‘Hetty, please be mine. I have never felt this way about a girl before.’ His hands are around my waist, but he begins to slide them lower and I say to him, ‘Walter, stop. I am not that sort of girl.’ And, of course, he does stop, because he loves me, but—

‘Hetty! What on earth are you waiting for? It’s so refreshing in here!’

Erna is treading water, her hair slick and dark as spray from the waterfall falls on her head.

‘Coming!’ I remove my boots and wriggle out of my skirt. The other girls fling off their clothes, right down to their undergarments, and leap into the water, shrieking and squealing, chattering and laughing. I peer into the black depths. You are a strong swimmer now, I tell myself, and remove my neckerchief, unbutton my sweat-soaked shirt and pull off my woollen socks one by one, carefully folding everything and finding a spot to place them neatly on the rocks, You have no reason to be afraid.