‘Please, Mr Bemrose, don’t look so shocked. We are here to give you a message, that is all.’

The man had addressed him in English with a Mittel-European accent.

‘Are you sure you’ve got the right person?’

‘You are Mr Bemrose, yes – a British official?’

Bemrose said he was, but he was sure he was one of many, and in any case how on earth had they found him here? He was wondering about heading back towards the path when he noticed the man – to his horror – reaching into his inside jacket pocket. He held his breath until he produced a silver cigarette case and offered it to him. He eagerly took one.

‘In September, Mr Bemrose, you looked after an Englishman and his wife who visited Berlin on official business. Please… do let me finish. They had reason to go to the Soviet sector of Berlin, where they had dealings with Commissar Iosif Gurevich.’

Bemrose started to say that he really couldn’t recall it, but the man held up his hand.

‘This isn’t a question, Mr Bemrose: I am stating matters of fact. This is a message from Iosif Gurevich: you are to contact the couple urgently and tell them he needs to see them in Berlin as soon as possible.’

‘Well, I suppose—’

‘It is also essential that you add it is in connection with Kestrel. They’ll understand. Perhaps you’d care to repeat the message?’

Bemrose did so, and then the couple said it had been very nice to meet him and shook his hand, slightly bowing their heads as they did so. Would he mind, they asked, if he waited where he was for ten minutes or so to give them time to make their way back?

The investigation in London had been going badly. Hugh Harper at MI5 gave the impression of being very put upon. He complained that he’d lost most of his influence and half his team, including the Disciples, as his elite team of watchers and followers led by the redoubtable Bartholomew was known – were being dismantled. He was wondering how long he had left in the Service, he told Prince.

Nonetheless, he had managed to secure the services of three officers – ‘all qualified accountants, would you believe’ – who specialised in investigating financial matters. ‘It sounds rather tedious, Prince, but these chaps insist that in investigations like this, money is the key to everything. They look at bank accounts and work out where the deposits have come from and where money paid out goes. They have had some very encouraging results. Let’s give them a fortnight: they’re confident they ought to dig something up.’

Despite their confidence, they didn’t manage to dig anything up. Bourne and Sons turned out to have two business accounts, one with Martins Bank and the other with the Midland Bank. MI5’s investigators looked at both accounts going back to the start of 1944: all the deposits by cheque or from other accounts were above suspicion, as was the money paid out. They’d then turned their attention to the personal bank accounts of Bourne and Ridgeway, the former’s with Midland Bank, the latter’s with National Provincial. Again they were unable to find evidence of any suspicious activity.