'Thank you,' Ben said simply. He looked around him. 'We need to get back to the road.'

Halima shook her head. 'No,' she told him. 'It would be too dangerous. There are too many bandits in this region. If they saw us by ourselves, they would kill us just for the clothes we are wearing.' Ben remembered Abele's words of warning – 'In the Congo, the only person safe from voleurs is the man with no money' – and with a shudder he recalled the man who had tried to rob them when they first arrived in the region.

'You're right,' he said. 'And anyway, Suliman will be expecting us to find our way back to the road. I'd be willing to bet he'll have people there looking out for us.' It was a devastating thought. The canopy above was impenetrable, the surrounding rainforest dense and inhospitable. Ben felt something crawling on his skin; he slapped the side of his face to get rid of it, but could feel a mosquito bite already welling up there. With a sinking feeling, he realized that he did not even know in which direction they needed to travel to get to the village.

As though reading his thoughts, Halima spoke. 'The road we took travels in a straight line west from the village. We are somewhere on the north side. But if we are to travel east, we will have to cross the river at some stage.'

Ben nodded.

'It will be very dangerous,' she told him seriously. 'Many wild animals live in that river, and you do not always see them until they are upon you. Perhaps there is another way.'

'What?' Ben asked.

'There is another village twenty miles to the west of here. We would not need to cross the river. Perhaps if we could reach it, I could get in touch with my sister and ask her to raise the alarm.'

Ben shook his head. 'We might be carrying the virus,' he told her. 'We can't risk spreading it to anywhere else. Besides, it's too far. We need to raise the alarm as quickly as we can.'

'But the river-'

'Listen to me, Halima. The first thing Suliman will do when he gets back to the village is inform his superiors in Kinshasa about what has happened. They will suspect that you'll try and contact your sister. She's in great danger. If we don't raise the alarm quickly, who knows what will happen to her?'

Halima fell silent.

'I'm sorry, Halima,' Ben said after a moment. 'But you need to know what we're up against.' He looked around. 'I have to get to the satellite phone in Suliman's office, and I can't do it by myself.'

Halima nodded her head gently. 'Tell me what you want me to do.'

Ben chewed on his lower lip. 'The first thing we need to do is get our bearings,' he said almost to himself.

'I can use the stars to navigate,' Halima told him. 'But in here…' She looked up meaningfully at the thick canopy overhead. They were not going to see the sky for a while.

'Then the only other way I can think of discovering which way is east is by watching the sun rise.' Ben joined Halima in looking unenthusiastically up at the trees above him. 'We'll never be able to do that from here,' he murmured.

'There are hills in this region,' Halima told him.

Ben understood immediately what she was saying. 'If we can get above the tree line,' he mused, 'we'll be able to see the sun setting and rising.' He stood up. 'Let's get a move on. We still have armed men tracking us, so we need to go quietly.' A thought suddenly came to him. 'What are the chances of there being landmines in the forest?' he asked.

'Small,' Halima told him. 'Most people are not so foolish as to come here.'

Ben wasn't sure if that was a comfort or not.

He stepped away in a certain direction. Suddenly there was an unholy scream. It wasn't particularly loud, but it was full of terror and pain, causing the blood to run cold in Ben's veins and the birds in the trees to fly away in a deafening flock of movement. Ben stopped in his tracks and looked back at Halima. 'What was that?' he breathed.

Halima looked grim. 'It could have been anything,' she stated. 'One wild animal killing another, I think.' She stood up and approached Ben, who had changed from feeling forced confidence to sudden fear. 'There is only one way to survive in the forest,' she told him seriously, 'and that is to accept its ways. If you start to fear it, or break its rules, it will consume you.' She looked above her, where the birds were settling back down in the trees. 'Everything that happens here happens for a reason. If you understand that, all will be well.'

Ben took slow, deep breaths, listening carefully to what Halima had to say.

'Most of the animals here will fear us,' she continued. 'But if we impose ourselves upon them, they will have no option but to attack us. And if that happens, they will be far more dangerous than foolish men with guns.' She walked deftly past Ben and pulled back a curtain of palm leaves that blocked their way. 'Follow me,' she whispered. 'And go quietly.'

Ben and Halima struggled through the jungle in silence, heading uphill whenever the opportunity presented itself. By now it was midday, and even though they were protected from the direct beams of the sun, it was still growing intolerably hot. Already the inside of Ben's mouth was becoming dry and leathery; he kept it firmly closed in an attempt to prevent moisture loss, but he was still desperately thirsty. They would need water, and soon.

All afternoon they struggled. At times they would stumble upon natural clearings where ordinarily Ben would feel safer, relieved of the all-encompassing oppression of the rainforest; but they knew they could not stay long in the open. There were men after them, and they had to stay hidden. After a couple of hours, though, they found themselves on a steady incline, and at one stage they had to scramble over rocks to gain height. The low evening sun was blood-red in the sky when they found themselves on the bald summit, above the thick line of the trees. They sat there catching their breath, watching the sun slip easily across the sky. When it was threatening to disappear, Ben pointed in its direction. 'West,' he said shortly. 'Or near enough.' He stood up and turned round a hundred and eighty degrees. 'So we need to travel in that direction. Or as near to it as we can – it won't be easy keeping our bearings.'

Halima came and stood next to him, and for a few moments they looked in silence over the vast expanse of the African rainforest. It stretched as far as they could see, undulating and magnificent, punctuated in places by mountainous peaks, elsewhere by deep troughs that seemed to be filled with hazy steam. They could still hear the noise of the forest from where they were, but it was peaceful nonetheless. 'It is very beautiful, is it not?' she murmured. 'When men disturb what has been here for so long, no good can come of it. It is no wonder the ancestors are angry.'

Ben turned to look at her. 'It's not the ancestors, Halima,' he said gently. 'It's a virus.'

Halima smiled. 'You have great faith in your science,' she observed. 'But answer me this. If a snake bites you at your home, what would you do?'

'Find a doctor,' Ben replied. 'And fast.'

Halima nodded her head. 'It is true,' she said, 'that a doctor might be able to cure you. But would he be able to tell you why the snake bit you? Or what it was doing at your home? Or who sent it?' She looked back over the rainforest. 'Scientists do not know everything that goes on in this world.'

Dusk was falling, and Halima's words were disconcerting. 'We need to find somewhere to sleep,' Ben muttered to change the subject. 'Maybe we should stay here – nobody will be able to see us in the dark.'

'No,' Halima said. 'Animals will be here after dark. They will smell us, and we will be too exposed. And besides, it will rain soon. We do not want to be caught in it. We need to get back down, find some shelter.'