A menagerie of warders lounged around the main entrance hall, and one of these, a pug-faced man smelling strongly of carbolic soap and carrying a bunch of keys that was about the size of the average car tyre, led me through a Cretan labyrinth of yellowing, toilet-bricked corridors and into a small cobbled courtyard in the centre of which stood the guillotine. It’s a fearsome-looking object, and always sends a chill down my spine when I see it again. Since the Party had come to power, it had seen quite a bit of action, and even now it was being tested, no doubt in preparation for the several executions that were posted on the gate as scheduled for dawn the next morning.

The warder led me through an oak door and up a carpeted stairway, to a corridor. At the end of the corridor, the warder stood outside a polished mahogany door and knocked. He paused for a second or two and then ushered me inside. The prison governor, Dr Konrad Spiedel, rose from behind his desk to greet me. It was several years since I had first made his acquaintance, when he’d been governor of Brauweiler Prison, near Köln, but he had not forgotten the occasion:

‘You were seeking information on the cellmate of a prisoner,’ he recalled, nodding towards an armchair. ‘Something to do with. a bank robbery.’

‘You’ve a good memory, Herr Doktor,’ I said.

‘I confess that my recall is not entirely fortuitous,’ he said. ‘The same man is now a prisoner within these walls, on another charge.’ Spiedel was a tall, broad-shouldered man of about fifty. He wore a Schiller tie and an olive-green Bavarian jacket; and in his buttonhole, the black-and-white silk bow and crossed swords that denoted a war veteran.

‘Oddly enough, I’m here on the same sort of mission,’ I explained. ‘I believe that until recently you had a prisoner here by the name of Kurt Mutschmann. I was hoping that you could tell me something about him.’

‘Mutschmann, yes, I remember him. What can I tell you except that he kept out of trouble while he was here, and seemed quite a reasonable fellow?’ Spiedel stood up and went over to his filing cabinet, and rummaged through several sections. ‘Yes, here we are. Mutschmann, Kurt Hermann, aged thirty-six. Convicted of car theft April 1934, sentenced to two years’ imprisonment. Address given as Cicerostrasse, Number 29, Halensee.’

‘Is that where he went on discharge?’

‘I’m afraid your guess is as good as mine. Mutschmann had a wife, but during his imprisonment it would seem from his record that she visited him only the one time. It doesn’t look like he had much to look forward to on the outside.’

‘Did he have any other visitors?’