'So where the fucking hell did you come from?' Nathan Holmes spat as the exhausted soldier and the group of six survivors entered the assembly hall. There were several other people in the room. They each individually stopped what they were doing and stared at the unexpected arrival. 'We were based just outside the city. Look, is there any chance that I could get...' 'Was it you who was shooting yesterday?' Holmes interrupted. 'Not me personally, but...'

'And the engine we heard, that was you too?' Cooper nodded, exhausted. Much as he understood why it was happening, this sudden interrogation was the last thing he needed. 'That was us,' he answered. 'Us?'

'That's right.' 'So where are the others?' 'Back at the base I hope.' 'And why are you still here?' 'We got separated.' 'How come you can breathe? Are the others immune?' Cooper shook his head. 'Don't think so.

I don't know for sure. I only found out I was by chance. Look, could somebody please tell me exactly what happened here? I've been...' 'Aren't you the one who should be telling us what's happened?' asked Donna. She walked across the room to stand directly between Holmes and the weary soldier. Cooper shrugged his shoulders. 'I don't know,' he replied. 'None of us knew. We had a little information, but nothing...'

'What information?' Jack Baxter asked, moving closer. 'Like I say, no-one knew very much,' he explained. 'We were told there was a disease. We knew that it was widespread and that it had probably killed thousands but nothing like...' 'So where were you when it happened?' 'What?' 'If you didn't know that you were immune until you got here, where have you been hiding for the last few weeks? How come the rest of you didn't get infected?'

'We were in a bunker.' 'You want to be thankful you didn't see any of it,' Bernard Heath sighed, sitting down a short distance away. 'What?' 'I said you ought to be grateful you were underground when it happen,' he continued. 'It was more than thousands of people that died, it was millions of them. Bloody millions of them just dropping dead where they'd been standing. Christ, I don't expect there's a thousand people left alive.'

'So what about the ones outside? Are they...?' Cooper let his words fade into silence. No matter what he'd witnessed out on the streets, he couldn't bring himself to ask the impossible question which had played on his mind since he'd first arrived in the city. 'They're dead,' Baxter answered. 'If I hadn't seen it myself I probably wouldn't believe it. They all died on the first morning.

A couple of days later they started to move again.' 'But how could they...?' Cooper mumbled pointlessly. 'Don't know. Christ, we've got a doctor here and he doesn't know either. No-one knows.' Phil Croft took Baxter's comment as his cue to become involved in the conversation. 'Your guess is as good as mine,' he said quietly. 'No-one's ever seen anything like this before so there's no point asking me what's happened. Tell you the truth, there's no point even trying to work it out.' 'Do you know what did it?' asked Paulette, the large and relentlessly effervescent lady who had been hanging on every word of the difficult exchange, hoping for answers.

Her normally bright and energetic voice was suddenly quiet and uncharacteristically serious and flat. Cooper shrugged his shoulders. 'No,' he admitted. 'Bloody hell,' Heath protested, 'you must have some idea.

Were we attacked? Was it an accident?' The soldier shook his weary head. 'I really don't know. It can't have been a missile attack because you'd have seen or heard something. I'd have heard something. We would have known if we were being attacked. We were trained to deal with that kind of situation.' 'So what are you saying?' 'I'm saying that this was different.' 'What about the speed of it?' Donna asked.

'I was nine floors up. I watched it move across the city. How could that have happened?' 'I'm starting to wonder whether it was already here,' Croft added. 'There's no way a disease or a virus could be carried on the wind that quickly, is there?'

'I've got no idea,' Cooper sighed. 'Look, I've got no reason to hide anything from you. If I knew anything then I'd tell you. Like I said, no-one that I was with seemed to know anything. There might be people somewhere who understand it all, but the officers in our base knew about as much as you do.' Weary, Cooper collapsed into the nearest chair. Donna handed him a bottle of water and pulled another chair across the floor to sit next to him.

There was a look of intense concentration on her face. Much as she was interested in the superficial and relatively unimportant details that Paulette and probably many others wanted to hear from the soldier, she wanted answers to other questions from him. Already her mind was working frantically, analysing what he had so far said and wondering whether this stranger might be able to bring some safety and stability into their bizarre and dangerous world. He had, it seemed, arrived in the city from a protected oasis of relative normality. 'So how many of you were there?' she asked. Cooper drained the bottle of water dry and wiped his mouth and cleared his throat before responding. 'Where? How many of us were here yesterday or...?' She shook her head. 'In the base. How many of you were in the base?' 'Couple of hundred I think. I'm not completely sure.

Three hundred at the most.' 'Room for any more?' 'Don't know. Could be.' 'And are there more bases?' He nodded. 'There were supposed to be more, but I don't know if anyone managed to get to them. I'm not even sure where they are. There's bound to be one close to the capital.' 'You must have some idea.' 'Why? I didn't know where our base was until I was in it. Look, these are the kind of places you don't know you're reached until you're standing on top of them. I've heard that some of these bunkers are in the middle of cities, others are more remote. Christ, you might have lived next door to one for the last ten years and not known anything about it.

' Phil Croft sat down next to Donna. 'If we could get to your base,' he began, the tone of his voice tentative and uncertain, 'would you be able to get us inside?' 'You're out of your fucking mind if you think I'm burying myself underground with the fucking army,' Nathan Holmes hissed from a short distance away. 'Completely out of your fucking mind.' Croft shot a quick, disappointed glance in his direction and then turned back to face the solider again.

'Would they let us in?' he asked again. Cooper couldn't answer with any certainty. 'They might,' he said quietly, 'but on the other hand they might not. They might not let me back in. It depends if the decontamination process works, I suppose. I left the base but I never made it back, did I? The others that left with me might not have been able to get back inside. If they couldn't remove all traces of the disease then they'd have left them on the surface. For all I know they might have let it in when we left. The whole bloody base might be dead by now.' 'What kind of protection did you have?' Donna asked. 'Inside or outside?' 'Outside.'

'Full body suits and the best breathing kits the government could buy,' he answered. 'So,' she continued, 'while you were away from the base you couldn't eat or drink or...?' 'Theoretically we could,' he interrupted, finishing her sentence for her. 'The suits were designed to let you eat and drink and get rid of waste but we didn't carry much in the way of supplies. We weren't intending to be above ground for too long.' 'What if those others can't get back into the base because their suit or their equipment's contaminated...?' 'They'll have left them on the surface.' 'To die?' 'Suppose so.' 'And did you know that when they ordered you to go outside?'

'No-one said as much but it doesn't take a genius to work it out, does it?' 'No wonder you're not rushing to get back.' 'Part of the job,' Cooper mumbled nonchalantly. 'And are you still on duty?' Croft quipped. The soldier shook his head. 'I quit,' he said, deadpan. 'I quit the moment I found out I could breathe. You don't have to spend long out here to realise the whole planet's dead. I figured I might as well try and make the most of the little freedom I've got left. They probably think I'm dead anyway.' 'Might as well be,' muttered Holmes.