‘My brief is to poke around, sir, as Gilbey no doubt told you. I’m good at being discreet, just observing from the sidelines. It may well be that you’re just having an awful run of bad luck with the agents you’re dropping in. But if there is someone passing on information to the enemy, I would hope I could spot them.’

‘So I understand. You start at Rodmarton Street on Monday. I’m putting you with Llewellyn Tindall; he’s our logistics man. There’s not much going on in the section he doesn’t know about. It’s up to him to ensure everything’s sorted out for our operations. Awkward character at times, bit of bad luck in France during the Great War, but damn good at his job.’

In the three days before he started at Rodmarton Street – there was a weekend in between – Hendrie had drawn a mental picture of Llewellyn Tindall: Welsh, obviously, no doubt short and with a loud voice, probably a socialist of the Methodist variety. He might try to convert Hendrie to socialism or Methodism, or even both.

He turned out to be nothing of the sort. He was tall, with an almost aristocratic bearing, slightly stooped, and he walked awkwardly, as if he were in pain. He spoke with a cut-glass English accent, the words he used sparingly so carefully selected and enunciated they sounded affected.

Lieutenant Colonel Webster had taken Hendrie into Tindall’s office on the Monday morning and left him there after the briefest of introductions. Tindall said nothing, nodding his head more in resignation than greeting, and pointed to a small desk opposite his own.

‘Miss Poulsen is my Danish secretary: she comes in late and stays late. She sits there.’ He tapped a large pane of frosted glass behind him, on the other side of which was a narrow outer office that Hendrie had entered through. ‘There are some files for you: read yourself in. It really isn’t terribly complicated here. There’s a briefing document on Denmark there too. You’ll need to look at that. Just remember that Danes are a variant of Germans and you won’t go far wrong.’

For an hour Hendrie sat awkwardly, the only sound being the turning of pages, the slight groans made by Tindall every time he moved, and a constant clearing of his throat. Every ten minutes or so he got up and took a few paces around the room before carefully lowering himself back into his chair.

‘My mother-in-law was Welsh,’ Hendrie said eventually. It was an attempt to break the silence, but as Tindall slowly looked up at him as if he were mad, he immediately regretted saying it.