He wouldn’t give a name, or a telephone number, but insisted it would be ‘worth my while’. He said the fact that I was from Hull, the fact that I’d survived the Hull Blitz, and my area of historical specialism – the bombing of Dresden – meant that I was the ideal person to bring this all out into the open. Little did I know how difficult that would be.

*

I found him in a tucked-away corner of the pub. He was already waiting for me. He was a nervous looking chap – quite slight, white-haired, perhaps late sixties or early seventies – with those round wire NHS specs that people only wear when they can’t afford anything else. His blazer was threadbare at the elbows too – which started alarm bells in my head. Perhaps that was what this was all about. Money. Or the lack of it, in his case. And the chance to earn some from me, in exchange for what he’d insisted in his letter was ‘historical dynamite’.

But as he explained the background to how he came to have the documents, I realised I was doing him a disservice.

‘It’s something I’ve felt guilty about all my life,’ he said, his voice barely above a whisper. It felt at the time almost like a piece of theatre – how could the events of nearly forty years ago still pose a threat now? But the man appeared genuinely frightened, and was determined our conversation shouldn’t be overheard. ‘Of course,’ he continued, ‘the Dresden bombing’s been exploited at times for propaganda. You know, the Nazis adding a zero to the death toll, taking it into hundreds of thousands rather than tens, then people like David Irving regurgitating those figures. But it was still a terrible, awful thing. And I witnessed some of the thinking behind it, and it’s always preyed on my mind.’

‘Witnessed how?’ I asked him.

‘During the war, I worked for Frederick Lindemann.’

‘Churchill’s chief scientific adviser? Viscount Cherwell?’

‘That’s right. Not a particularly pleasant man. Brilliant, but arrogant – like a lot of top people in their field. Anyway, I was his secretary. Everything he was involved with passed my desk. Including the psychological study in Hull for which you were one of the subjects.’

I looked at him aghast. ‘You know that I was involved?’

He nodded. ‘I remembered your name.’ Southwick’s not that unusual a name in East Yorkshire, but perhaps for a mandarin from the Home Counties, it would have stood out. I felt myself start to shake then, the memories of Fred coming back, the memories of that meeting with the man from the Ministry in the front room, how I lost it with him, and then the belting from my father.