But there were too many unspoken words between us and I knew I couldn’t say any of them. To do so would mean facing up to what all of this really meant. It would mean admitting that our promises of friendship for ever were a lie – and I wasn’t ready to do that. Not yet.

‘Look, I – I’ve got to go.’ Max glanced furtively around. ‘Everything will be okay,’ he said.

‘I’m sure it will,’ I replied. As he ran back to the classroom, I wondered if he believed it any more than I did.

I couldn’t go home. The school day still hadn’t ended and I couldn’t bear the thought of telling my parents what had happened and why I was home early. So I walked. I went to the park, to the canal, around the streets, walking and walking until my legs burned and my hands were so cold I could barely feel them.

Shame followed me around every corner, clinging to me like a dark shadow. A host of questions weren’t far behind. What had happened today? Why had it happened? Who had made Mr Schmidt behave like that? Had he always hated us and just pretended not to? And what about everywhere else? Other schools? Was it just our school where this had happened? Was it happening in Czechoslovakia? Was Elsa going through the same thing?

Since she’d left, we’d exchanged a few letters and cards. They got shorter each time. A few words on a piece of paper were no match for the reality of a best friend living a few streets away. But still, I thought about her every day.

For the first time since she’d left, I was glad she wasn’t here. At least she was spared the horror of what had happened to me today.

Finally, after wandering for a while, it was four o’ clock and I could go home without having to answer any questions.

I made my way through the city, blowing on my hands to keep warm as I walked through the cobbled streets. As I neared Stephansplatz, the main square in the middle of the city, I heard noise up ahead. I turned into the square and looked around. There was a crowd of people at the far end. What were they doing? It sounded like they were having a party. Pushing and jostling each other as they cheered and laughed.

So, rather than cutting across the centre of the Stephansplatz to get home as I would normally do, I made my way to the far end of the square to see what was happening.