The all-clear sounded just before seven-thirty. It was virtually dark now, and with the black-out regulations strictly in force it was hard to make out the buildings on the other side of the street. Earlier that day Russell had checked the weather and moon for the coming night - a clear sky was expected, with a quarter-moon rising soon after midnight. By that time, he hoped, everyone concerned would be safe in bed.
The two of them drank some warmed-up soup, and watched the clock tick slowly by. Eight-thirty - the Isendahls and their two friends should be setting out from Friedrichshain. Eight forty-five, and it was time for them to leave. Effi put a summer coat over the nurse's uniform, and Russell packed his helmet and armband in an old carpet bag. They walked downstairs and out into the night.
It really was dark, much darker, Russell thought, than during the previous exercise, and by the time they found the lorry he was beginning to wonder if they would ever find anything else. But the white-painted kerbs and the slitted beams of light did make a difference, and once they reached the Ku'damm it became clear that visibility was better on the bigger streets. All those cracks of lights added up, Russell guessed. He could think of no other reason.
It took them about ten minutes to reach their destination, a stretch of road by the Landwehrkanal, close to the Lichtenstein Bridge which connected the Zoo and the Tiergarten. Russell drove slowly past the vehicle that was already parked there, and made out the cross on its side.
He u-turned the lorry at the intersection with Rauch-Strasse and pulled up behind the fake ambulance. As he climbed down there was a loud screech from inside the Zoo.
'The animals don't like the darkness,' Wilhelm said, materialising out of it. He had managed to get himself an armband, and so, Russell discovered, had Max and Erich. And in this light Freya's uniform looked very convincing. After introducing Effi to the others as Magda, Russell said as much.
'We fooled one policeman already,' Wilhelm said. 'He came past about ten minutes ago, and wanted to know what we were doing here. I told him we were waiting for our commander, that he'd brought his son on the first call-out and was dropping him off at home between air raids. He believed me, thank God. I didn't want to shoot him.'
'You have a gun?'
'Of course.'
Russell didn't know what to say. He could hardly blame the man, but... 'Only in the last resort,' he insisted.
'Of course.'
Russell handed him the two spare number plates and a screwdriver, and held the torch as Wilhelm swapped them with the ones on the van. Once that was done, he addressed the assembled company, feeling like a gang-leader in a bad Hollywood film. 'All right. So we know what we're doing. We set off when the next raid begins, or at eleven if it still hasn't started. Max and Erich will come with me, Magda will travel in the ambulance with Wilhelm and Freya. No second names - the less we know about each other the better.'
They had less time to wait than Russell expected. Shortly before ten o'clock the roar of aeroplane engines brought forth the sirens, and these in their turn triggered a cacophony of screams, mewls and roars from the occupants of the neighbouring Zoo. Seconds later the flash of anti-aircraft fire from a nearby roof caused even more consternation, and Russell was convinced he heard the trumpeting of an elephant. As another volley of skybound blanks threw spasms of light across the road and canal they moved off in convoy, the lorry leading the way.
It was little more than a kilometre to the top end of Eisenacher Strasse, but the lack of lighting restricted their pace to a near crawl, and Russell had to circle Lutzow-Platz twice before he found the right exit. Once on Eisenacher Strasse it was a matter of judging distance, and trying to recognize familiar landmarks. Russell was beginning to worry that he had come too far when he spotted the sawtooth roof of the bookbinding factory.
He pulled up alongside the row of houses opposite and climbed down, just as a flight of planes flew noisily over. In the silence that followed faint voices and music were audible, and as his eyes grew more accustomed to the darkness he saw cracks of light where windows must be. The slitted beam of his torch revealed the number of the building in front of him. It was 403.
There was no noise from within, which seemed like good news. He walked round the corner of the building and found an empty space where the cars had stood. That was good news.
The others had gathered on the pavement, and the combined light of their muted torches created a pocket of half-light. A collective halo, Russell thought. How fitting.
He walked up the steps to the front door and used the brass door-knocker, loud enough, or so he hoped, to bring a reaction without rousing the curiosity of the whole street.
No one answered.
He banged again, louder this time. Beside him, Effi looked anxious.
This time there was a response. Footsteps inside, the click of a bolt being drawn back, a spillage of light as the door edged open.
Russell shoved his way through, causing a cry of consternation from within. Effi and Wilhelm followed. 'Air Raid Protection,' Russell barked at the man who was struggling back to his feet. 'This house has been bombed. I want everybody out. Now.'
'That's not possible,' the man said, but there was a welcome lack of certainty in his tone. Thin, balding and bespectacled, he was wearing a bizarre mixture of clothes, a civilian shirt and tie with police trousers and boots. 'You do know that this is SS property?' he almost pleaded.
'I don't care whose it is,' Russell told him. 'Targets are chosen at random, and it's a criminal offence to obstruct an Air Raid Protection unit in the course of its duties. Now, what is your name?
It was Sternkopf.
'Well, Herr Sternkopf, how many people are there in this house?'
'Four. Five including me.'
'How many women?'
'Four.'
Russell breathed an inner sigh of relief. 'Get the other lads,' he told Wilhelm. They had decided beforehand that the two of them would deal with any outside interference while Max and Erich searched the house.
'I must telephone Standartenfuhrer Grundel,' Sternkopf was saying.
Russell rounded on him. 'Herr Sternkopf, this is a serious exercise. If British bombers do attack Berlin there'll be no time to make telephone calls. Now please, this way.'
Sternkopf hesitated, but only for a second, as Russell escorted him outside. Max and Erich, who passed them on the steps, had already laid out the half-dozen stretchers which Wilhelm had borrowed from one of the few remaining Jewish clinics in Friedrichshain.
'Lie down on one of these,' Russell ordered. Sternkopf did so, and Freya hung a home-made placard around his neck that bore the words 'severe head injury'. She then squeezed some of the fake blood that Effi had borrowed from the studio onto the side of his head. 'It has to be realistic,' Russell told him sternly. 'Please moan as if you are in real pain.'
The front door opened again, spilling light across the pavement, and Russell saw Sternkopf staring at him, as if keen to remember what he looked like. 'Let's get him in the ambulance,' he told Wilhelm. 'It'll make it harder for him to remember our faces,' he added in a whisper.
They lifted him in, reminded him to moan, and shut the ambulance door. On the pavement, two young women were being told to lie down on stretchers. As far as Russell could make out in the gloom, both were young, dark and quite probably Jewish, but neither matched his picture of Miriam Rosenfeld. Both were wide-eyed with fright, and Effi was kneeling beside them, asking their names and quietly explaining that they were involved in an ARP exercise. She and Freya had insisted that telling the girls what was really happening would be more likely to panic than reassure them.