‘Persistent bastards, aren’t they?’ said a voice at his side. Ben hadn’t heard anyone climb up the rocks. Only Jaden Wolf could sneak up on him like that. Wolf’s expression was as hard and keen as a hunting predator. His battle face. He took the binocs from Ben and studied the faraway dust plume. ‘You ever disturb a wasps’ nest?’

‘Something’s got them all worked up, that’s for sure,’ Ben said. ‘And they’re not giving up easily.’

‘I suppose this is our payback for wiping out their pals. How the hell did they track us this far?’

Ben was considering the alternative possibility that something worse might have happened. That was, whether someone could have got to old Karim at the institute and made him reveal Madison’s whereabouts to them. If word had got out about the American woman who had managed to slip out of the city, aided by two Afghan men officially considered as suspect and even traitorous, evading a number of patrols on their way across country, it might well have occurred to some Taliban higher-up that the American would make a fine trophy hostage for them, with big ransoms to be extracted from back home – while at the same time making an example of her collaborators. He hoped nothing bad had happened to the old guy. He decided not to say anything to Madison, Aziz or Ramin about it.

‘We should move on,’ he said to Wolf.

Some of the group took the news better than others as they quickly got underway again, but nobody was quite ready to panic yet, and even Ramin settled down after Madison assured him that everything would be okay. Holt took the wheel from Ben and Baldacci relieved Wolf in the Humvee.

For the next few hours they made steady progress heading due north-west. By midday their pursuers seemed to have receded further behind the horizon. Come late afternoon, they stopped once again to clamber up a hillside for another observation and could see no trace of the dust plume anywhere.

‘Looks like we gave them the slip,’ Holt said with grim satisfaction, narrowing his eyes against the rays of the slowly dipping sun.

‘Maybe,’ Ben replied. ‘For now, anyway.’

‘We got bigger fish to fry, buddy. Let’s move on. Four more hours and we’ll stop and make camp.’