There was no panic in the private dining room of Das Bayerischer Haus. Once the woman in the beret had disappeared, Kurt pointed to the hidden door in the panelled wall and they filed towards it. It opened onto a steep stone stairway, lit from the top by a bright bulb, which revealed an iron rail running down the wall. They gathered together at the top of the steps as Kurt closed the door behind them, quietly sliding three sets of bolts into place. No one had said a word, though everyone was breathing hard.

‘It will be safer to turn out this light,’ said Kurt, his voice little more than a whisper. ‘Walk down slowly, one step at a time. Just make sure you don’t let go of the rail. Are any of you armed?’

They all shook their heads.

‘I’ve got my Mauser; I’ll go first. What’s that?’

They listened in silence: the muffled noise seemed to be coming from the room they’d been in.

‘We’d better hurry. When we reach the bottom of the steps, I’ll open the door. You’ll find we’re in a back yard. It’s not the yard to the restaurant, which will be to your left, on the other side of a high brick wall. Once we’re all out, I’ll lock that door – you’d better give me the key, Bruno – and then we’ll go our separate ways. Come on, let’s move.’

The descent was a perilous one in the pitch dark; the steps, as well as being damp and slippery, were also of varying heights, making their progress slower than they would have liked. Behind them they could hear some kind of commotion. Kurt was at the front, Prince behind him, followed by Otto, with Bruno at the rear. Kurt waited until they were all at the bottom before sliding open the single bolt.

The yard was empty, and although it was dark, it was possible to make out their surroundings: two large dustbins ahead of them and the high wall Kurt had mentioned to their left, behind which was the rear entrance to the restaurant. They could hear voices coming from that yard. To their right was a tiny passageway that led to the street.

They closed the door and Kurt locked it, placing the key in one of the dustbins. Somewhere in the distance they could hear shouting, and a dog barking. He gathered them in a huddle and pointed to the passageway.

‘That opens on to Lindenstrasse,’ he whispered. ‘I’ll turn left, which will take me back towards Donhoff Strasse. Bruno, you turn right and then into Kommandantenstrasse. You two carry on down Lindenstrasse. You’re at the Excelsior, correct? Well, keep going until you see Koch Strasse: that will lead you back towards Askanischer Platz. We’d better hurry now.’