A Traffic car stood guard on the road side of the bridge. But someone had done a good job of torching the Shogun. It was difficult to tell what colour the scorched paintwork had been, but for a few streaks left on the boot and around the front wings. The interior, though, looked relatively undamaged.

Cooper looked around the area. The last glance at the map had given him an idea.

‘There’s not much we can get from the car until the SOCOs arrive,’ he said. ‘I’d like to take a look up this way, Georgi.’

‘Very well. Your sergeant says you know everything about this area.’

‘She does?’

‘Yes, indeed. Sergeant Fry must regard you very highly.’

Cooper laughed. ‘I don’t think you’ve known her long enough. It probably wasn’t a compliment.’

Though Kotsev’s stride was longer, he obviously wasn’t used to walking over rough terrain, and definitely not uphill. He was panting in minutes. That was a sign of too much city living, in Cooper’s view. No matter how big their muscles were, a forty-five-degree slope always sorted the men from the boys.

‘Where are we going?’ gasped Kotsev, stopping to rest and watching Cooper moving steadily away from him.

‘Just to the top of this rise.’

‘Chaga, chaga. Wait.’

‘What’s the matter, Georgi?’

‘I think the air is a little thin here.’

‘We’re not even a thousand feet above sea level.’

Kotsev began to move again, but awkwardly, planting his feet with great deliberation on the rough grass. His knees were probably hurting by now, if he never used the right muscles.

A moment later, Cooper was standing at the top of the slope, letting the breeze cool his forehead. To the north east, he could see a drystone wall running along the skyline, marking the road between Wirksworth and Middleton. He followed the wall a little further north – and there was the distinctive outline of a red phone box.

He smiled. When public phone boxes were first designed, they were painted bright red to stand out from a distance. For decades, it had been important to know where the nearest phone was, and these old kiosks would have been a welcome sight. They weren’t used a lot nowadays. But they were such an integral part of the landscape that they were kept in the countryside as a conservation measure, as much as for emergency use.

Finally, Kotsev struggled the last few yards and arrived alongside him, breathing heavily and wiping sweat from his forehead.

‘Georgi, how many people in Bulgaria have mobile phones?’ asked Cooper.

Kotsev stared at him. ‘Everybody, except for those who are too poor. And the very old, who don’t understand them.’

‘Yes, it’s the same here. And even if you don’t own a mobile, you have a phone in your house. Not many people are too poor or too old for that.’

‘What are you saying?’