The military police were on the streets, stopping people and demanding papers. They worked in threes, forming summary courts, and were mainly interested in men of fighting age. They did not bother Carla in her nurse’s uniform.

It was strange that in this blasted cityscape the apple and cherry trees were gorgeous with white and pink blossoms, and that in the quiet moments between explosions she could hear the birds singing as optimistically as they did every spring.

To her horror she saw several men hanged from lamp posts, some in uniform. Most of the bodies had a card hanging around the neck saying ‘Coward’ or ‘Deserter’. These had been found guilty by those three-man street courts, she knew. Was there not already enough killing to satisfy the Nazis? It made her want to weep.

She was forced to take shelter from artillery bombardments three times. On the last occasion, when she was only a few hundred yards from the hospital, the Soviets and the Germans seemed to be fighting only a few streets away. The shooting was so heavy that Carla was tempted to turn back. Hannelore was probably doomed, and might already be dead: why should Carla add her own life to the toll? But she went on anyway.

It was evening when she reached her destination. The hospital was in Iranische Strasse, on the corner of Schul Strasse. The trees lining the streets were in new leaf. The laboratory building, which had been turned into a transit camp, was guarded. Carla considered going up to the guard and explaining her mission, but it seemed an unpromising strategy. She wondered if she might slip inside from the tunnel system.

She went into the main building. The hospital was functioning. All the patients had been moved into the basements and tunnels. The staff were working by the light of oil lamps. Carla could tell by the smell that the toilets were not flushing. Water was being carried in buckets from an old well in the garden.

Surprisingly, soldiers were bringing wounded comrades in for help. Suddenly they did not care that the doctors and nurses might be Jewish.

She followed a tunnel under the garden to the basement of the laboratory. As she expected, the door was guarded. However, the young Gestapo man looked at her uniform and waved her through without questioning her. Perhaps he no longer saw any point in his job.

She was inside the camp, now. She wondered whether it would be as easy to get out.

The smell here was worse, and she soon saw why. The basement was overcrowded. Hundreds of people were packed into four storerooms. They sat or lay on the floor, the lucky ones having a wall to lean against. They were dirty, smelly and exhausted, and they looked at her with dull, uninterested gazes.

She found Hannelore after a few minutes.

The doctor’s wife had never been beautiful, but she had once been a statuesque woman with a strong face. Now she was gaunt, like most people, and her hair was grey and lifeless. She was hollow-cheeked and lined with strain.