Henderson looked uncomfortable. ‘I would have liked to for the sake of Digby Clarke’s kids, but Mannstein was more important. He could have recreated his plans within weeks and the Germans would have shipped him off to Poland before I could possibly get back from Tours.’

‘So if we can’t get to Tours before Potente we’re stuffed?’

‘Not necessarily,’ Henderson said. ‘We’ll have to pray that some of the phone lines out of Paris are still working. If they are, we might be able to get a message down there.’

Marc looked surprised. ‘But I don’t even know the name of the person they’re staying with, let alone the phone number.’

‘I know,’ Henderson said, nodding. ‘But you said they were staying with a retired priest on a farm south of Tours. That might be enough – for the sakes of Paul and Rosie Clarke, it had better be.’

‘So if we’re not going to Tours, where are we going?’

‘There’s a telephone exchange just a few hundred metres from here. They’ll have phone and street directories for the whole of France. We need to get in there, but it’s likely to be under guard to prevent saboteurs.’

‘Sounds great,’ Marc said, as a drop of blood trickled from his chin on to his white shirt.

CHAPTER TWENTY-EIGHT

Marc hunkered in the footwell of the sidecar as Henderson rolled up outside an office building. The carved wooden door had a brass plaque bearing the logo of France Télécom. A single German infantryman guarded the door, but he only seemed interested in the finger jammed up his nose and he was stunned by the sight of Henderson in Gestapo uniform. He bolted to attention and gave an anxious salute.

‘Heil Hitler,’ Henderson said, as he accepted the salute with a flick of his wrist. ‘I have orders from Oberst Hinze to access the directories and switchboard inside this telephone exchange.’

The infantryman nodded. ‘Very good, Herr Major. One of our engineers is working inside and should be able to assist you.’

‘Boy,’ Henderson shouted, as he looked back towards the sidecar.

Marc sat up. ‘Please don’t hit me again, sir,’ he said meekly.

The guard was shocked by the sobbing boy with blood pouring down his chin, but it only served to enhance his opinion of the Gestapo. Regular German troops feared the black uniforms almost as much as the civilians in the countries they occupied. So while the baby-faced guard found the situation odd, he had no intention of quizzing a Gestapo officer.

The inside of the exchange was stuffy, with the smell of sparks and oil in the air. Henderson led Marc across a reception area and under an archway to a dim space lined with racks containing thousands of mechanical switches. Over a third of Paris’s telephone traffic went through this exchange, with each call connected by the shuddering racks of gears and cogs.