‘Back outside,’ Ilse said.

They stepped into the corridor. Carla closed the door all but a crack, and peeped through. She saw Herr Römer and another man push a hospital trolley through the doors.

The men did not look in Carla’s direction. They were arguing about soccer. She heard Römer say: ‘It’s only nine years ago that we won the national championship. We beat Eintracht Frankfurt two-nil.’

‘Yes, but half your best players were Jews, and they’ve all gone.’

Carla realized they were talking about the Bayern Munich team.

Römer said: ‘The old days will come back, if only we play the right tactics.’

Still arguing, the two men went to a table where a fat woman lay dead. They took her by the shoulders and knees, then unceremoniously swung her on to the trolley, grunting with the effort.

They moved the trolley to another table and put a second corpse on top of the first.

When they had three they wheeled the trolley out.

Carla said: ‘I’m going to follow them.’

She crossed the morgue to the double doors, and Frieda and Ilse followed her. They passed into an area that felt more industrial than medical: the walls were painted brown, the floor was concrete, and there were store cupboards and tool racks.

They looked around a corner.

They saw a large room like a garage, with harsh lighting and deep shadows. The atmosphere was warm, and there was a faint smell of cooking. In the middle of the space was a steel box large enough to hold a motor car. A metal canopy led from the top of the box through the roof. Carla realized she was looking at a furnace.

The two men lifted a body off the trolley and shifted it to a steel conveyor belt. Römer pushed a button on the wall. The belt moved, a door opened, and the corpse passed into the furnace.

They put the next corpse on the belt.

Carla had seen enough.

She turned and motioned the others back. Frieda bumped into Ilse, who let out an involuntary cry. They all froze.

They heard Römer say: ‘What was that?’

‘A ghost,’ the other replied.

Römer’s voice was shaky. ‘Don’t joke about such things!’

‘Are you going to pick up the other end of this stiff, or what?’

‘All right, all right.’

The three girls hurried back to the morgue. Seeing the remaining bodies, Carla suffered a wave of grief about Ada’s Kurt. He had lain here, with a sticking-plaster on his arm, and had been thrown on to the conveyor belt and disposed of like a bag of garbage. But you’re not forgotten, Kurt, she thought.

They went out into the corridor. As they turned towards the back door, they heard footsteps and the voice of Frau Schmidt. ‘What is taking those two men so long?’

They hurried along the corridor and through the door. The moon was out, and the park was brightly lit. Carla could see the shrubbery where they had hidden the bikes, two hundred yards away across the grass.