There were terrible storms that week and our balconies were the best places to watch the strange weather in Anhalt. The lightning strikes were prolific, and lit the snowflakes blue, and the wind so fierce that the snow appeared like tiny birds thrown this way and that. It was a wonder not much settled, but in the mornings the snow wasn’t much more than sugar, and it was gone by noon, and the day could be placid, even bright, until the weather changed again and the sky resembled a nineteenth-century painting of ships lost to the boiling sea.

I was on my balcony with my coffee and cigarette watching one of these electrical shows when there was a knocking I didn’t recognise. My first thought was that it would be Franz – he’d taken an interest in me since our night in Walter’s room and I suppose his attentions were quite flattering. But when I opened the door I saw instead a courier in uniform, and the embroidered logo on his overalls stirred my memory. There were wet patches on his shoulders where the snow had melted. His face was smooth. Without meeting my eye he said he had a delivery for Mr König.

‘His room’s upstairs.’

‘He’s not in. No one’s in. Can’t you take it?’

‘What is it?’

He gestured at the box, about a yard by a yard, and I realised the logo was from the same courier company Ernst had used. ‘All right. Leave it here.’

He asked for a signature, which for some reason I was reluctant to give. I would have preferred it if Mr Steiner had forgotten me completely, and I put down a scrawl. The courier scowled, looked at my nameplate, and printed beckermann and my Christian name too, so all of my efforts anyway were for nothing.

‘Leo?’ I said, suddenly remembering.

‘No,’ he said, scowling. ‘That’s not me.’ Without a further word he pushed the box into my room and left.

Before Walter’s package was even in the room I knew I wouldn’t be able to resist peeking inside. I slipped the padlock to ‘1919’ – thinking that Mr Steiner would surely have changed the code by now – but it worked first time.

There was a burst of excitement: what could be inside? At the top was one of Charlotte’s bog paintings that neither Walter nor I had liked. I wondered why he had kept it, and why Mr Steiner had sent it. Underneath were navy ledgers, the kind that had been everywhere around the studio. Inside them were compositions, measurements and portraits of some of the painters, a few of whom I recognised.