Sam nodded and began to climb, not knowing whether he'd be able to do it himself. While he knew it was true that neither of the girls possessed his brute strength, he wouldn't have fancied taking on either of them in a fight. With the image of the crocodile still looming large in his mind, he was relieved a few seconds later to hear first Xian Mei and then Purna start to ascend behind him.

At least fucking crocodiles can't use ladders, he thought.

The climb seemed twice as long as the descent, and by the time he reached the top of the shaft Sam's muscles were trembling with fatigue. He paused a moment, sweat running down his face. His arm was throbbing where the zombie in the supermarket had bitten him, and so was the back of his head where he'd hit it on the side of the counter. Ideally he could have done with something to eat and drink, maybe some painkillers and a few hours' sleep to recharge his batteries. He knew, however, that he wasn't going to get any of that any time soon. Instead he was somehow going to have to dredge up the energy to launch an attack on the heavily armed low-lifes who had killed Dani and taken Jin hostage. This time yesterday he hadn't even met any of the people currently in the building above him or clinging to the ladder below. Now it seemed they occupied his whole life.

Wrapping his left arm round the topmost iron rung set into the wall of the shaft, Sam took several deep breaths in an effort to stop himself feeling dizzy, then tilted his head back as he directed the flashlight beam upwards. He saw a circular indentation directly above his head where a manhole cover should be, but the manhole cover wasn't there. Instead, laid across the top of the hole was what looked like wood.

Floorboards, he thought, his spirits sinking. In the intervening years, someone must have laid a wooden floor over the original stone flags. Transferring the flashlight to his left hand, he adjusted his position to reach up and push at the underside of the wooden floor. He expected there to be no give whatsoever, and was astonished when the wood rose easily above his hand.

It took him a moment to realize it wasn't a wooden floor above him after all, but a trap door or, more likely, a trap door set into a wooden floor. He allowed the door to settle back into place and briefly told the girls what he had found.

'Can you open it?' Purna asked.

'I think so.'

Sam pushed again and the trap door rose. When it had risen to the extent of his outstretched arm, he climbed up and out, attempting as he did so not to drop the flashlight or impale himself on the machete which he had tucked into the belt of his jeans. He half-expected to find himself surrounded by guys pointing guns at his face, but instead he emerged into what seemed to be a janitor's office. There was a sink, a mop and bucket, various tools and cleaning implements on shelves, and an armchair with a newspaper folded on the seat.

He turned to help the girls out and then lowered the trap door back into place. Purna crossed the room and put her ear to the door. 'I can't hear anything,' she said.

'Could be this ain't even the right building,' Sam said.

She puffed out her cheeks at the prospect and Sam knew that, despite her focus and drive, she was as fatigued as he was. 'Let's see, shall we?' she said.

Once she and Sam were in position, Purna nodded and Xian Mei plucked open the door. Purna and Sam stepped out quickly, turning in opposite directions, guns poised. However, the corridor they stepped into was dark and quiet, and although a brief examination revealed the floor to contain little more than a staff locker room and shower block, it was obvious from the stickers on the lockers and the wording on a staff shift chart on the wall that they were in the right place. As if further proof were needed, at the far end of the corridor was a reinforced fire door with a keypad on the wall beside it, above which a sign read CELLS 112. Idly Purna tapped in the four-digit security code 4274 that had failed to open the main door earlier, and was not surprised to find it failed to open this one either. Retracing her steps, she pushed open a set of double doors on to a stairwell and the three of them cautiously and silently began to ascend.

The sign on the wall next to the double doors of the floor above read G. Although that presumably stood for 'Ground', Purna guessed that because of the steps outside, which led up to the main door, it was more likely to be the floor above this one where they had first entered the building, and the one above that where they had encountered the three men. She whispered as much to Sam and Xian Mei and they nodded their agreement. The trio ascended another flight, and then another, whereupon Purna crossed to the double doors and peered through the reinforced glass panel set into it. Recognizing the corridor leading to the open-plan office where the men had ambushed them, she turned to check that Sam and Xian Mei were ready, then pushed the door open a few inches.

She slipped through the gap quietly, checking left and right. The door to the office was about three metres to her right on the opposite wall of the corridor. Purna crossed the corridor swiftly, turned to flatten herself against the wall and sidled along it to the door. She waited until Sam and Xian Mei were beside her, then she peered around the edge of the glass door.

She saw the men immediately. They had cleared one of the desks and were sitting around it, playing cards. She saw Jin too. The girl was huddled against the opposite wall, hands and feet tied, face bruised and streaked with tears. Purna saw the oldest of the three men, the one with piggy eyes who had fired at them out of the upstairs window, raise his head and call something across to Jin, his voice rough and mean. Jin cowered, lowering her head, and the other men laughed. Trying not to let her anger cloud her judgement, Purna saw that the older man and the tattooed man had replaced their hunting rifles with Heckler and Koch MP5 submachine guns, presumably from the police armoury. The weapons were propped against their chairs, within easy reach should the need arise. Because the scrawny man was on the far side of the table, Purna couldn't see where his weapon was, or whether he had replaced his original handgun with something else. She drew her head back and told Sam and Xian Mei what she had seen and how she thought they should handle the situation. Again, and without hesitation, both nodded their agreement.

Purna took a slow deep breath, composing herself, then nodded. The three of them stepped away from the wall, moving into position. Purna nodded once more, then strode forward and kicked the door open, raising the shotgun as it flew back. Before the men with their backs to her had even turned round, she barked, 'All of you, raise your hands! Do it now!'

She didn't glance round to see if Sam and Xian Mei had moved into position on either side of her; she trusted them to have followed her instructions. She was focused only on the three men, on what they would do with their hands.

When the tattooed man twisted and reached for his gun, Purna shot him.

She did it without hesitation, blasting a hole in his back. There wasn't a coin-sized wound and a trickle of blood like on the TV. Instead, a chunk of flesh tore away from between his shoulder blades, shattering his spine and causing blood to gush from him like a punctured water bag. He collapsed forward, his face smashing against the edge of the desk as his chair tipped over. When, a split-second later, the older man jumped up and clawed vainly for his gun, which had already toppled to the floor because he had stupidly knocked it over when he had moved his seat, Sam shot him in the stomach.

The scrawny man, meanwhile, snatched a handgun off the table beside him. The handgun had been hidden from view by the older man's body, and the scrawny man actually managed to raise it an inch or two before a flare, fired by Xian Mei, exploded in his face. He screamed and went over backwards, but still managed to squeeze the trigger of his gun as he fell, the bullet dislodging a chunk of plaster from the ceiling. To ensure he wouldn't be able to get off another lucky shot, Purna adjusted her aim, tilted the shotgun down and to the left slightly, and shot him through the heart.

The echoes of the gun battle seemed to reverberate in Sam's ears for far longer than they should have done. It was only when they finally began to abate that Sam realized the room wasn't as silent as he had thought. Huddled against the wall, Jin was sobbing hysterically, her hands covering her face, and the man Sam had shot was whimpering and clutching his stomach, his hands and shirt slick with blood.

As Xian Mei went over to comfort Jin, Purna walked forward, cursorily examining the two dead men and then looking dispassionately down at the wounded man at her feet.

'Please ...' he whispered. 'Please ...'

'Sorry,' Purna said, her voice flat and dead, 'but there's nothing we can do for you. You can either lie here and die slowly in pain, or we can make it quick.'

The man's eyes widened. 'No ...' he whispered. 'You can take me with you ... Please ...'

Purna shook her head. 'We can't carry you and you're too badly wounded to walk. Sorry, but that's just the way it is.'

'Please ...' the man whispered again, his world suddenly reduced to nothing but a desperate desire to survive and a terrible fear of death. 'Please ... please ...'

Purna sighed and slowly, wearily began to load her shotgun.

'No,' Sam said, walking towards her.

She looked up at him, her face expressionless.

'No,' he repeated, reaching out and putting a hand on her arm. 'It ain't fair you should do this. Not again. It's someone else's turn.'

She stared into his face, her eyes so deep and penetrating that Sam couldn't help but think she could see all the way down into his soul. He turned away from her gaze, but was still aware of her eyes on him, and of the weight of the gun in his hand.

'It's my turn,' he said quietly.

Chapter 12.

MYSTERY MAN.

'OPEN UP. IT'S us.'

Purna and Xian Mei scanned the area like border guards, while Jin waited in the van and Sam thumped the door of the lifeguard station with his clenched fist. It was almost noon now and the sun was at its peak.

From here Banoi looked beautiful. To their left the stretch of powder-white beach edged a sparkling blue crystal sea, while to their right the lush vegetation rose towards mountains whose summits glowed a soft purple where they met the bright and cloudless sky. A warm breeze blew in from the west, kissing their skin and tempering the heat of the sun, and despite the chaos in town, the only sounds that disrupted the midday tranquility were the languid calls of exotic birds.

If not for the individual parts of a dismembered body scattered in bloody profusion further along the beach, it might almost have been possible to believe that the events of the past twelve hours were nothing but a terrible nightmare. Sam was about to thump on the door again when Logan's voice replied, 'Who's "us"?'

Sam rolled his eyes. 'Stop messing about, man. It's dangerous out here.'

There was the heavy chunk of disengaging locks and the door opened. Grinning, Logan said, 'Sorry, no hawkers, no traders and definitely no blood-drenched zombie killers.'

Sam matched his grin with a tired one of his own and said enticingly, 'We got Twinkies.'

'Oh well, that's different,' Logan said, and pulled the door wide.

The four of them trooped in, Purna immediately discarding her weapon no longer the shotgun, but an HK G36 assault rifle appropriated from the police armoury and slumping into one of the seats around the table. Jin shuffled in like an old woman with her head down, Xian Mei's free hand (in her other she was also carrying an HK G36 assault rifle) round the younger girl's shoulders. Sam, who had stood aside to let the women in before him, walked over to the table and dropped a big bag of pastries and cakes on to it.

'We brought breakfast,' he said. 'They were all out of skinny muffins, so if anyone's on a diet, tough shit.'

'You, my man, have got class,' Logan replied, closing and locking the door. 'Hey, Sinamoi,' he called. 'How 'bout some coffee for our guests?'

Sinamoi was hunched over the radio, headphones on, twiddling dials, but at Logan's words he looked up and grinned. 'Sure. I make coffee.'

As Sinamoi bustled about, Purna squinted tiredly up at Logan. 'You look better.'

'You don't,' he replied cheerily. 'Added to which if I could just raise a little personal hygiene issue here you guys stink.'

Sam sniffed his sleeve and recoiled. 'That's not us, that's zombie.'

Logan shook his head. 'It'll never catch on.' Pointedly he looked at his watch. 'So what took you so long? I was beginning to think you'd abandoned me and I was going to have to live out the rest of my days in this two-bit shack with no one but Sinamoi for company hey, no offence, man,' he called across to the lifeguard, who grinned yet again and raised his hand in acknowledgement.

Over cake and coffee, Sam, with Purna and Xian Mei butting in at regular intervals, told Logan their story. When he got to the part where they had encountered Jin, Logan gave a crooked smile and said softly, 'I wondered when they were going to get round to you.'

Jin didn't reply. She didn't even raise her head.

'Don't say a whole lot, do you?' Logan muttered.

Xian Mei said quickly, 'She's been through a bad time.'

To everyone's surprise, Jin suddenly looked up, her eyes black and glittering. In a voice shaking not only with trauma, but also with barely suppressed rage, she said, 'I was raped by three men. They killed the man who was trying to protect me, and then they beat me and raped me. And they kept beating me and raping me until I passed out.'

Silence followed her words. Logan looked away, shaking his head.

'Shit, man ... that's ... shit. I mean ... that's fucking awful, man ... sorry ...' he mumbled.

Jin took a shuddering breath and said, 'I used to have faith in people, you know? And faith in God too. Even after Mama died, I thought ... I thought that the good in the world was stronger than the bad, and that eventually evil would be vanquished. But now ' she shook her head 'that sounds so ... so pathetic ...' Her voice tailed off and she lowered her head again. Xian Mei reached out and gently stroked her back.

Sam grimaced and carried on with the story, his voice a low rumble. He told Logan about killing the men in the police station and rescuing Jin, about stocking up on weapons from the armoury, then going back to the church and delivering provisions and medicine and weapons to Sister Helen's rag-tag group of survivors.

'It seemed weird taking guns to a church,' Sam said, 'but in a way those guys are fighting God's war, I guess ... fighting against the demons.'

'The infected aren't demons,' said Xian Mei. 'They're victims, like everyone else.'

Sam shook his head. 'That's not what I meant. That thing that's got inside those people that's the demon. The people themselves ... well, they're dead. They're just shells.'

'No such things as demons,' muttered Purna. 'What's got inside them is just a virus, that's all. A germ. There's nothing biblical about it. It's not evil. Only people are evil.'

Sam shrugged. 'Well, I guess that depends on what you believe.'

The expression on Purna's face suggested she was prepared to take the argument further. To prevent her from doing so, Xian Mei said quickly, 'So what about you, Logan? Has anything happened here?'

Logan raised his eyebrows. 'Apart from the clam bake and the beach volleyball tournament, you mean? Yeah, our mystery man's tried to get in touch a couple times. Reception was so bad, though, he didn't make a whole lot of sense. Said something about the satellite transmitters being down and some fucking offshore storm causing radio interference. You ask me, it's here where the fucking storm is.'

'He say anything else?' asked Purna.

'Only that he'd try to call back around noon today.' He glanced at his watch. 'Hey, which I guess is about now.'

They all looked at the radio expectantly, but it remained silent. They had to wait another fifteen minutes before it crackled into life.

Instantly Sinamoi scuttled across and put on the headphones. He twiddled dials and knobs, trying to get the best reception. At first the voice trying to get through was so engulfed in static they couldn't make out what it was saying. A few more tweaks from Sinamoi and all at once it came through loud and clear.

'Hello,' it was saying. 'Hello, can anyone hear me?'

Logan nodded at the chunky old microphone on its stand, his raised eyebrows forming a question, and Sinamoi nodded. Talking into the microphone whilst simultaneously carrying it over to the table, its long lead trailing behind it, Logan said, 'Hearing you loud and clear. Well ... clearish anyway.'

'Who is with you?' asked the voice. 'Is everyone safe?'

Logan glanced around. 'Yep, the gang's all here.'

'And everyone is safe? No one has been infected by the virus?'

'Well, it's pretty hard to tell with Sam,' Logan said, earning himself a finger and a grin in response, 'but ... yeah, they all seem pretty healthy.'

'How come you don't already know?' Purna said challengingly. 'I thought you were monitoring us? Last time you called you seemed pretty aware of our movements.'

'Nothing sinister in that,' the voice reassured her. 'We simply have some extremely powerful monitoring equipment here. We're able to intercept satellite signals from anywhere on the island, including CCTV footage. Unfortunately the satellite transmitters are behaving somewhat erratically at present. Adverse atmospheric conditions, I'm told.'

'And where's "here" exactly?' Purna asked.

'Please,' the voice said, 'as I explained before, our windows of opportunity for speaking to one another are so limited that you must refrain from asking quest-'

'Fuck that,' interrupted Purna. 'You expect us to trust you for no reason? To follow your instructions blindly?'

'I'm trying to help you,' the voice said.

'Yeah, that's what you say,' muttered Sam.

'See, the thing is, we've been talking,' Purna said, 'and we're maybe not as stupid as you'd like to believe.'

'I don't think you're stupid at all,' said the voice smoothly. 'On the contrary, I believe you to be intelligent, resourceful individuals. That's why I think you have a chance to escape from this mayhem and that's why I'm prepared to help you.'

'Bullshit,' said Sam with feeling.

'Sam's right,' said Purna. 'You don't want to help us because we deserve it for being so resourceful. You want to help us because we're immune.'

There was a moment's silence. Purna looked round at the others, a quietly triumphant look on her face.

'Nothing to say?' she asked.

The owner of the voice sighed or perhaps it was simply a surge of static and eventually replied, 'All right. I admit there is some truth to what you say-'

In a rare burst of anger Xian Mei suddenly blurted, 'You caused this! You or whoever you're working for! You manufactured this situation! And you threw us into the mix just to see what would happen!'

'No!' the voice said, shocked. 'No, it wasn't like that at all.'