Unterlüss was a typical small German town, dependent on the factory, with tall half-timbered buildings with steep sloping roofs and the serious-minded Saxon inhabitants. Reputedly the hardest workers in the country, their neighbours had a saying for them, that in a Saxon household ‘even if Grandfather is dead he must work; put his ashes in the timer’.

The name he had been given was that of the factory manager, Herr Gessler, and having rung from Celle he was expected. Gessler was very correct, dressed in a grey suit that hugged his thin frame, with rimless glasses and his party badge on his lapel, an object he was given to frequently fingering. A tour of the factory was obligatory and it was something he would report back on, this being the manufacturing works for not only small arms and flak artillery, but for small-calibre naval guns.

Gessler had obviously been told to treat him as an honoured guest, an instruction which had no doubt come from above, but he was nervous in a way that made Jardine jumpy, given there seemed no reason for him to be. He was also a walking technical encyclopaedia who wanted to impart all his knowledge in a sort of breathless litany that left even a man with a professional interest in the subject wondering whether he would ever shut up.

The nerves had an explanation, which was provided as they approached the head office building having finished their tour. The Mercedes standing outside had a swastika pennant on its wheel arch and beside it, standing to attention, was a driver in the pale-blue uniform of the Luftwaffe.

Inside Gessler’s office they met the passenger – a full colonel, sharp-featured and wearing a monocle, in a beautifully tailored uniform, boots so shiny you could have shaved in them, and a pair of grey gloves in one hand which he slapped into the other – who, having clicked his heels, introduced himself as Oberst Brauschitz.

‘Herr Moncrief, I have come from Oberbefehlshaber Göring who wishes to meet with you. I am ordered to convey you to his hunting lodge at Carinhall.’

He did not want to go; it was like the lair of the wolf and he was aware that the excuse he offered was a feeble one. ‘I daresay that will involve an overnight stay, Herr Oberst, and my luggage is at the Fürstenhof.’

Brauschitz responded with a thin smile. ‘Please credit us with some sense, Herr Moncrief. Your luggage is in the back of the car. But I assure you, were it not, you would want for nothing, given the person who is going to be your host.’

‘I cannot think I warrant the personal attention of the supreme commander of the Luftwaffe.’

For the first time the genial mask dropped and he almost barked. ‘It is not for you to decide, it is for you to do as you are requested.’

There was no point in saying it did not sound like a request, even less in continuing to refuse. ‘Herr Gessler, I thank you for my tour and I am sure I will be seeing you shortly in the near future.’ That was followed by a keen look, to see if he agreed; if he did not, Cal knew he was in trouble. All he got was a sharp nod, which left him still guessing.

‘Shall we go? My superior does not like to be kept waiting.’

That was an absurd thing to say; Cal did not know exactly where Carinhall was but it lay in a totally different region of Germany, further away even than Berlin. That was when he found out how they were going to get there.

‘I take it you have no exception to flying?’

‘None.’

The plane was a Fieseler-Storch, and once his case was in, there was not a lot of room. Brauschitz had replaced his service cap with a flying helmet and they were airborne very quickly. The noise inside the cramped cabin made talking extremely difficult, so Cal just sat back and admired the scenery as they flew fairly low over the countryside. On landing there was a second car waiting and now the colonel could talk.

If he was urbane, it was in a German way; correct and, in his case, slightly boastful. By the time they reached their destination Cal knew he was part of a military family that went back a long way, and that he was related to very many senior officers in the German army, including one on the General Staff. Fortunately, with it getting dark and the road being through thick forest, which shut out what light was left, he was unable to see the look of boredom on his passenger’s face.

The so-called hunting lodge looked more like a low-lying Florida to Jardine; thatched roof, white walls and two storeys high. It stood in extensive grounds, proved by the time it took to travel past the steel-helmeted Luftwaffe guards at the stone-pillared gate and get to the house itself, which was lit up like a luxury hotel. Dominating the gravelled courtyard was a bronze statue of a huge wild boar. Inside, Cal’s first impression was of overdecoration, not that he had long to look; a white-coated valet came in carrying his case and the colonel indicated he would take him to his room.

Once there, the man proceeded to unpack his things and hang them up, and that included his dinner jacket. ‘Dinner will be served in an hour and dress is informal, mein Herr, shall I lay out what I think appropriate?’

‘Please do.’

‘With your permission, I will take the rest of your clothes when you have changed and have them sponged and pressed.’

‘Thank you.’

The fellow was a perfect servant, except when he was finished and about to depart he gave Cal a crisp, full-armed, Nazi salute.

The two-fingered response was only produced when he had gone.

In a blazer and open-necked shirt, Callum Jardine still felt overdressed compared to his host, who was clad in a long, sleeveless hunting waistcoat of soft brown leather, green trousers and he too was in a white shirt and tieless. Never having seen Göring outside of newsreels, it was interesting to observe he was thinner than he looked on film, although still well built. The smile was the same, though, a full affair that pushed out his cheeks, rosy either from fresh air or the unnecessary fire in the huge grate.

‘Herr Moncrief.’

‘I don’t quite know what to call you, sir.’

Göring went over to a table full of bottles and, having established that Cal would drink whisky and water, made it for him. Interesting that in a house full of servants, this conversation was not going to be overheard by anyone. The glass, crystal, weighed a ton but the whisky was a single malt.

Göring laughed and finally replied to the question. ‘As long as you do not call me what they do in the part of Spain from which you have come. That, I do not think, would be flattering.’

‘No. That would be rude.’

‘Sit, Herr Moncrief, and tell me something of yourself.’

This was a situation in which Lizzie’s brother’s true story was no good. He was a lounge lizard who worried whether his tie matched his spats, never quite deciding, and letting his man do it for him after an hour of agonising. A life spent in the clubs of St James seeking to outbore the bores; that tale was not going to impress this man.

Added to that, Hermann Göring was no fool; he could not have got to his present position if he was. In the dog-eat-dog pit of Nazi politics he was a top man, and that also meant he was a ruthless killer. For all the smiles and the amiable expression he could have Cal taken out like a shot without blinking.

‘I don’t think it will surprise you to know that is not my real name.’

‘No.’ Göring waited, only speaking when Cal did not. ‘Am I to be told what your real name is?’

‘I rather suspect you might know already. You do, after all, have a great deal of resources with which to check up on people.’

‘Captain Callum Jardine.’

‘Not a serving captain and I never use that rank.’

‘You’re an interesting fellow, but I cannot see why you have become involved in this particular transaction. My information, which I will admit to you is limited, does not have you down as a fellow traveller of communists.’