Hassad nodded, pointing to the underside of the tooth. Porter's vision was still fuzzy, and the pain ripping through his head was making it hard for him to concentrate. The painkillers were still a long way from kicking in. But he could see a sliver of dark matter on the underside of the tooth.

'Silicon,' said Hassad. 'A micro tracking device, sending out a signal that can be picked up by a satellite.'

'Bastards,' Porter muttered. 'They promised me I was going in clean.'

He could feel the anger burning inside him. He'd walked into the Firm voluntarily. He'd put himself into the line of fire for them, because he wanted to get Katie out. And this was how they repaid him. By putting a tracking device into his tooth, and then trying to kill both of them. And just so they could save face.

Hassad chuckled. 'Never trust the British government,' he said. 'That's a lesson we learnt out in this part of the world a long time ago.'

TWENTY-SIX.

The truck had Jordanian number plates, and it looked empty. That means it is on the way home, Porter decided. Completely the opposite direction to us. He checked that the driver was still in the cafe next to the shop, then knelt down, pulling out a piece of chewing gum he'd found in the Fiat, and carefully sticking the tooth to the underside of the lorry. 'That'll take care of them,' he said, glancing back at Hassad. 'Collinson's boys will spend half the day searching for this vehicle, and when they catch up with it, they'll just have a Jordanian truckie and bunch of empty crates.'

They climbed back into the Fiat. Hassad had taken the wheel, explaining that he knew the roads better, and was less likely to attract attention from other drivers. As they'd left the old woman's house, they had borrowed a burka for Katie. It covered up her face effectively, and it made sure no one would recognise her as they drove towards the border.

It was close to mid-afternoon. After an hour's drive, Hassad had suggested they stop for some food, and wait for darkness. They were fifty miles from the Israeli border by now, and Hassad was convinced they needed to plan their breakout. The strip of land between Lebanon and Israel was used by Hezbollah to launch its rocket attacks on its neighbour. The territory was swarming with fighters, making it one of the most heavily militarised places on earth.

'Where's the best place to get through?' asked Porter.

While they were still in the van, Hassad pointed to the map the driver kept on the front seat. 'Here,' he said.

Porter glanced down. Beit Yahoun. It meant nothing to him.

'Never heard of the place,' he said.

'It's a border village, and one of the main crossing points between Lebanon and Israel,' said Hassad. 'There used to be about ten thousand people living there, but the place has been shelled to bits over the years. There are about a thousand people there now, and most of them are soldiers.'

'Can't we sneak through somewhere a bit quieter?'

Hassad laughed, but his expression quickly turned serious again. 'Quiet? On the IsraelLebanon border?' He shook head. 'There is no such place. Every inch is heavily fortified, and if the soldiers see you, they shoot you on sight. That goes for the Israelis as well. They see us coming through the wire, they'll open up their machine guns, and worry about who the hell we are later on.'

'And you think this Beit Yahoun place is safer?'

'There's a demilitarised zone of about a mile, a bit like the no-man's-land that used to exist between the Berlin Wall and the West. There isn't much trade or traffic that goes between Israel and Lebanon, but what there is, mostly goes through there. Get into the no-man's-land, and we should be able to walk through to Israel without being shot.'

Porter glanced around. 'Then let's go,' he said.

'Not yet,' said Hassad.

Porter checked the time. It was just after four in the afternoon. The execution was scheduled for eight, and he'd have wanted to get Katie out of this hellhole long before then. 'When?' he snapped.

'We have another fifty miles to travel, and the roads aren't great,' said Hassad. 'Plus there are roadblocks to get through. It will take us about six hours. We stay here about two more hours, and travel when it's starting to get dark. It's safer that way.'

The time passed slowly. They stayed in the van. Porter managed to buy some more painkillers, and swallowed most of the packet. They would make him feel drowsy, and slow his reaction times if they came under attack, but it was better than the terrible pains that were still throbbing through his jaw and up into his head. Porter tried to nap. Sleep was impossible, however. He was too wired up. Another few hours, he told himself. Then I can get Katie out of here, deal with that fucker Collinson, and start getting on with the rest of my life.

As soon as we get back to Britain, I'll reveal that man's treachery to everyone.

And maybe even see Sandy again.

By six, it was getting dark outside. Hassad judged it was safe for them to start moving again. After buying some bottles of water and some food from the cafe, they loaded themselves back into the Fiat van. Hassad took the wheel, while Katie sat between then, her face completely covered by the burka. Porter had tucked the AK-47 underneath his feet, but he made sure the mag was full again, and that he could reach it within a couple of seconds. They could have used the ammo that had been destroyed back at the safe house, Porter thought bitterly, and another couple of guns. If it hadn't all been blown up by Collinson's men.

The first hour passed without incident. The road was long and straight, and there wasn't much traffic around. The weather was clear enough. It was turning cold, and there was some cloud spitting across the night sky but the half-moon would occasionally break through. It is always the same, thought Porter. The closer you get to the end of a mission, the more you long for home.

It was close on seven in the evening by the time they turned due south. The road they were on snaked along the border, and would eventually take them all the way down to the coast. The road was terrible. The surface of the tarmac was regularly broken up into rubble. For the past couple of years, the Israelis and Hezbollah had been shelling each other across this narrow strip of land, and the Israeli tanks had rolled through it, decimating everything they encountered. There were a couple of villages along the way, but they had long since been abandoned: just collections of empty, crushed buildings, without even any wild dogs still living in them. After ten miles, there was a single petrol station, but it only had two pumps, the price was double what it was in the rest of the country, and the owner had put up a steel bunker to hide the payment kiosk. Territory doesn't get much more hostile than this, thought Porter. And we're driving straight into it.

'If anyone stops us, just leave the talking to me,' said Hassad.

They managed another ten miles without any trouble. The roads were practically empty. The Fiat slowed down to a crawl. There were so many potholes in the road it was impossible to take the van much above ten or fifteen miles an hour. A couple of times, Porter had to climb out and push when a back wheel dropped into a shell hole. The chickens squawked furiously as he pushed, and Porter suggested ditching them, but Hassad said it would look better if they had some kind of cargo. As they progressed steadily on, Porter could sense that Katie was becoming more and more afraid. She'd been living with death for a week now, but she still hadn't learnt how to handle the fear. On the rare occasions a truck or a car passed them in the other direction, he could feel her shaking. She's right on the edge, Porter realised. Much more, and she's going to fall completely to pieces.

'Roadblock,' said Hassad. His voice was tense and strained.

Porter peered into the darkness up ahead of them. He could see a couple of cars pulled across the road. Next to it there was a brazier with some hot coals in it, where some men were keeping themselves warm. In total, there looked to be about three men, all with AK-47s hung over their shoulders. But there could be many more lurking in the background.

Hassad slowed the Fiat to a crawl. Between the two cars, a long wooden plank had been placed, and beneath that there was a net studded with nails. You could try to ram your way through, but the nails would blow out your tyres. You'd be easy meat for the gunmen standing right behind you.

'Leave this to me,' whispered Hassad.

A man was leaning into the side of the car. Hassad wound down the window, and they exchanged a few terse words in Arabic. Katie was sitting still, her face covered by the burka, while Porter had wrapped a scarf he found on the floor of the van up high around his neck. In the dark, with the weather-beaten appearance his skin had had ever since he started sleeping rough, it wasn't hard for him to pass for an Arab. Even so, his hand was under the seat, holding the AK-47.

The door opened. The soldier's gun was raised, and he was snapping something at Hassad, but Porter couldn't follow the conversation. Another soldier walked over. An older man, Porter judged. Thirty maybe, with a close-cropped black beard, and eyes as hard as steel. He tapped the younger man on the shoulder, and leant forwards. Porter glanced across. It was clear that he recognised Hassad. They exchanged greetings but there was no warmth there, Porter noted. More words. Then suddenly the door slammed shut, and Hassad had fired up the engine. The plank and the net that were slung across the road were removed, and the Fiat was moving on again.

Porter remained silent, but inwardly he was breathing a sigh of relief. He took a quick look back, making sure they were a safe distance from the roadblock and that no one was following them.

'Do they know Katie's escaped?' he asked.

Hassad shook his head. 'Not yet, but they might soon. Apparently a lot of communications are down because of the missile strike, and it's going to take a few days to get them back up again. Until then, they won't know that she's out.'

'That should make things easier for us.'

'Maybe,' said Hassad with a shrug. 'Or maybe nobody has spoken to the guys at this roadblock. We don't know about the next one.'

'Just so long as we get out here,' said Katie, speaking through her burka.

'We will,' Hassad snapped. 'Trust me.'

They picked up some speed. The road flattened out as they put the roadblock behind them. There were fewer potholes in the tarmac, and the landscape looked less damaged. On the left-hand side of the road, they were snaking close to Israel: at some points it was perhaps only twenty miles to the west of them. Another hour or so to the border point, Hassad told them. It was nearly nine now. They should hit it at around ten.

The Fiat pushed on into the darkness. Nobody was speaking. Porter was scanning the road ahead, keeping a watch out for more Hezbollah patrols. There were miles of empty countryside, broken only by the occasional small village. He saw some vans go by, and a couple of private cars. At one point he saw a truck full of Hezbollah fighters, their arms bristling with weapons, but they paid no attention to the van. As the countryside rolled by, Porter was thinking, planning. The pain in his mouth was terrible, the jawbone aching in a dozen different places, but he knew he had to concentrate on what happened next. With any luck, in the next couple of hours they would get across the border into Israel. But could they get in touch with the British Embassy in Tel Aviv, or would that just alert Collinson?

'Does Sky have a correspondent in Tel Aviv?' he said to Katie.

'Of course,' she said. 'Jamie Breakton. You'll get him at the Tel Aviv bureau. If he's not answering, I can call the Fox News bureau, or The Times The Times's guy.'

'Then we'll ring him just as soon as we get over the border.'

Katie pushed her burka aside, and Porter saw her face for the first time in hours. There was still a starved, vacant appearance to her eyes, but her strength and confidence were steadily recovering.

'The sooner we get this story on the air the better. The reason is, we can't trust the British government, not with that fucker Collinson on the loose,' said Porter, shaking his head. 'Get Sky News to pick us up rather than the embassy, and we'll be OK. If Collinson wants to shoot us, then he'll have to do it live on TV.'

'He wouldn't '

'He bloody would,' Porter snapped. 'He's already tried to kill us twice. Me, three times.'

The town of Beit Yahoun loomed up in the distance. A few lights, and some smoke rising in the air were all there was to mark it out from the rest of the desolate landscape. Porter saw the road sign, and then the outskirts of the place itself. The road worsened as they pulled into the first street leading down towards the demilitarised zone. The tarmac was cracked in so many places it might have been better to get out and complete the trip on foot, Porter thought. Along the way, there were the remains of houses, but they had been shelled virtually to oblivion. All that was left were the foundations, and the heaps of rubble that had collapsed into them. There were no street lights working, but about a mile away there were some streaks of neon shooting up into the night sky.

'The demilitarised zone runs for about a mile to the west of here,' said Hassad. 'Get into there, and we'll be OK.'

'Any checkpoints?' asked Porter.

Hassad nodded. The strain was evident in the man's eyes, Porter noted. He was delivering them to the border, just the way he promised. But now he was up against his own people, and you could tell that troubled him. 'One, and it's heavily guarded,' he replied. 'But we got through the last one, so we have to hope for the same again.'

The suspension on the Fiat was creaking as it ploughed through the potholes in the road. Porter reckoned the machine wouldn't hold out much longer. You needed an off-roader and preferably a jeep for this kind of territory. As they drew closer to the checkpoint, he could see a few men on the streets, but they were all soldiers or militia. Either the civilians had fled or they were cowering in their houses.

'Just keep your faces covered, and don't say anything,' said Hassad. 'I'll take you to the border, then drop you there and make my own way home.'

Porter nodded.

Even if I wanted to say something, my mouth hurts too much, he thought.

At his side, he could feel Katie shaking. He gripped the side of her arm to provide some reassurance: the fear was getting to her, the same way he had seen it get to Collinson seventeen years ago. 'Just try and hold yourself together,' he whispered. 'We'll be out of here soon.'

The checkpoint was brightly lit. There were two big wooden watchtowers, reaching thirty feet into the sky, each one with a searchlight flashing onto the ground. Porter glanced up. A machine gun was placed in the centre of each tower, on a pivot so that it could fire in any direction. The road led to a gate. There were two sentry posts on either side of it, and beyond that the empty desolate scrubland of the demilitarised zone. Cross that, Porter told himself, and we're safe.

'What's your story?' said Porter, glancing across at Hassad.

'My story?'

'You've got to give them some reason why you're driving a van into Israel. What is it?'

Hassad paused. 'Medical supplies,' he answered. 'I'll tell them we're delivering some blood.'

'With a couple of dozen chickens in the back?'

Hassad laughed. 'This is the Lebanon. Everyone trades in chickens on the side.'

Porter looked back ahead. There were two soldiers manning the sentry posts, and three more checking the vehicles moving through. It was just before ten at night, Porter noted. Not a time when many people were likely to be attempting to get across any border, never mind the boundary between Lebanon and Israel. There was no more dangerous crossing anywhere in the world, he thought. No one would try to get through it unless they had to.

Back in Britain, people would be anxiously waiting for news about Katie. They might be starting to suspect something had happened. So far, however, they would have no idea what.

Two vehicles were parked at the side of the road: one van and one car. The car looked to be empty, and the van's driver was standing outside it, smoking a cigarette. No traffic was coming through from the Israeli side. Hassad had pulled the Fiat up, but left the engine idling. One of the soldiers was walking towards them. Porter pulled the scarf up high around his neck, and made sure that Katie's burka was drawn completely across her face. His hand was dropped beneath the seat, cradling the tip of his AK-47.

The soldier's eyes flashed through the cabin of the Fiat. He was no more than twenty-five, with a clean-shaven face, and close-cropped black hair. But from the neat creases to his uniform, Porter reckoned he was some kind of Rupert, or Mustafa, or whatever the hell they called them out in this place. He was looking closely at Katie, his eyes running over her head, and down the length of her body. She was sitting rock still. How do they feel about lifting a burka round here? Porter wondered. In Britain, the border police are too politically correct, but I reckon around here they don't give a toss. If they want to take a look they will.

The soldier snapped a couple of brief commands at Hassad.

Hassad tried to smile, then shrugged and muttered a few words in reply.

The soldier barked another command. One of his colleagues walked over from the gate, and stood right behind. His finger, Porter noticed, was twitching on the finger of his AK-47. No more than a teenager. Trigger-happy didn't even begin to capture the look on his face. Trigger-bloody-ecstatic, Porter told himself grimly.

He gripped harder on the tip of his own assault weapon. Every muscle in his body was poised for action.

Another series of barked commands. Hassad was arguing, his face turning red. Then he suddenly smiled. He turned to look at Porter. 'They're letting us through,' he said. 'You're out of here.'

TWENTY-SEVEN.

Hassad slammed the door of the van shut behind him. Porter watched as the man walked slowly back into the Lebanon. He wasn't so bad, Porter thought. He did what he said he was going to do, and you couldn't ask for more from a guy than that.

Shifting across to the driver's seat, he grabbed hold of the wheel and tapped his foot on the accelerator. Up ahead, the gates were starting to swing open. The road stretched into the demilitarised zone, and there was one more set of Hezbollah guards on the other side, but they had already been cleared, and Porter wasn't expecting any trouble from them.

'We've made it,' he said, looking at Katie. 'We're back.'

He could see the relief flooding through her. 'Thank Christ for that.'

Porter drove slowly. It was a mile across the demilitarised zone, and then they would have to get through the Israeli border controls as well. Driving too quickly would only make the guards suspicious, Porter warned himself. Better to take it gradually.

The Fiat slid through the gates, which shut quickly behind them. Just ahead, about two hundred metres in the distance, Porter could see a guard flagging them down. The man was six feet tall, wearing a Hezbollah uniform, with some kind of scarf covering his face. He was holding an AK-47 in his arms, and motioning for the van to pull over.

'Shit,' Porter muttered.

'What does he want?' Katie asked anxiously.

'How the hell should I know?'

Looking ahead, Porter wondered whether he should jam his foot on the accelerator, and make a dash for the Israeli border. He could see the one guard flagging them down, and two more men standing behind him. To the side, there was a small hut that seemed to be serving as a sentry post, but could be hiding more men. The Fiat wasn't in bad shape, but it was still only a van, and there wasn't much acceleration in the engine. The chances of getting away were minimal.

'Maybe they only want some paperwork,' said Porter.

He slowed down, pulling the Fiat to a stop at the side of the road. The tall soldier was walking towards him, his pace deliberately slow. Act casual, thought Porter. Don't try and pretend to be an Arab, you'll never fool them. Just tell them you need to get to the other side. Fast.

The man was standing right next to the van now. The two other soldiers were standing astride the road, their faces also masked, but with their guns gripped to their chests. In the blink of an eye, they could shatter the van with bullets, Porter realised. There's no escape.

He wound down the window. 'Good to see you again, Mr Porter,' said Perry Collinson. 'For a while there, we thought we'd never bloody find you.'

Porter froze.

The words had sliced straight through him, like a dagger cutting through his skin.