I let my gaze travel to the table. What lay on top was barely recognizable as human. Parts of the skin were gone, exposing muscle and, in the case of her left thigh, the bone. Tracts of skin along the side of the face had been stripped away. Her clothes were gone. I noticed the table on which she lay was smoking intermittently as acid from her body ate into the surface.

I glanced at Chris. The sight obviously left him shaken. He could have ended her torment in the moment before Fielding's people had taken over.

He hadn't. I tried to imagine how he must be feeling now. I failed.

Thankfully.

'What's happening to her?' Chris's voice was a whisper. Fielding said quietly, 'We're not sure. Several reactions are taking place in her body.

Calcium sulphate is being reduced to calcium oxide and sulphur. The sulphur is poisoning her as it replaces the oxygen in her system. Somehow sulphur dioxide is forming in there, and when it combines with water - for example in her eyes - it turns to sulphuric acid.' Fielding took a breath, looked away for a moment and then back. 'The doctors are trying to keep her alive using sodium hypochlorate and organic alkaline in combination, both externally and internally.'

'For G.o.d's sake, why?' Chris's voice boomed in the confined s.p.a.ce of the observation corridor. 'Can't you see she's in agony?'

'I should imagine she's in h.e.l.l. But she's the only one who knows how to make the serum.'

I looked back into the lab, at Imorkal, staring down at the dying woman, remembered him yanking information from my brain as I might take a toy from a naughty child. They were keeping her alive in the hope he could reach in and get the formula before she died. In the moment I realized this I also detected that she was looking at me. No. She was looking at Chris.

Her eyelids were gone now, one eye was missing as well. The other stared fixedly at Chris. Her mouth moved in a series of jerks. The commsystem brought the gurgling remains of her voice to us. '- b.a.s.t.a.r.d - cuh - killed - You b.a.s.t.a.r.d, you could have killed me.

I looked away, said, 'Can't you take blood from us? We're cured., 'That was the first thing the doctors did. We have a solution which slows the rate of infection somewhat; but that only delays the inevitable.'

'The inevitable what?' I had a good idea what the answer might be. Fielding didn't disappoint me.

'The inevitable infection of the entire Earth.'

I blinked. The sentence was simple. Direct. Yet it meant nothing to me.

Fielding could have been describing a Neapolitan ice cream for all the effect it had on me. Chris was breathing fast. He was staring through the gla.s.s into the isolab. He seemed distant. I had never seen him scared before. At least I a.s.sumed he was scared. I was beyond terror. So I thought.

Chris licked his lips. 'I've seen this before. It's a terraforming virus. It's programmed to use what it can from an environment to recreate another.

Creation and destruction all at once.'

Fielding seemed about to speak when a red light flashed above the window. At the same time a siren cut loose.

A recorded voice said mildly, 'Attention. Seal breach in isolab One. Seal breach in isolab One. Evacuate adjoining areas. Repeat. Evacuate adjoining areas. Please remain calm.'

I noticed the personnel within the room go into an immediate panic. Too late. The doors their pressure suits were connected to slammed shut, sealing the tunnels to prevent exposure to the lab environment. It was obviously a measure designed to maintain the integrity of the lab and quarantine the doctors in case of infection. It did no good. In a matter of seconds their suits were blooming with yellow crystals.

I watched them begin to die.

One fetched up against the window. His suit was sprinkled with yellow crystals. Yellow powder puffed into the air as he hit the gla.s.s? The radio brought his voice to us clear as a bell. 'It's hot! The acid is hot! It's infectious! Get the h.e.l.l out and sterilize! Do it now before - The technician fell out of view. His face mask was melting from the inside. The scream was cut off as the radio circuit broke, remaining only distantly through the window. Distant but growing louder as the gla.s.s melted.

And as the gla.s.s melted a figure smashed its way through. Imorkal. He seemed unharmed, but his breath hissed painfully in his throat.

The recorded voice added mildly; 'Attention. Seal breach in isolab One.

Seal breach in isolab One. All adjoining areas are now hot. All adjoining areas are now hot. Sealing the lab unit for self-destruct sequence. Please remain calm. Your cooperation is appreciated.'

Beside us Fielding suddenly fell against the wall, a moan building in his throat.

'Get us ... out ... now...'

Chris and I grabbed an arm each. His clothes were beginning to burn. The air stank of acid fumes. My skin was on fire again. We staggered down the corridor with Fielding between us. Halfway to the end the door began to close. Imorkal moved ahead and blocked it. Motors whined then shorted out. The door froze.

The recorded voice said, 'Attention. Seal breach in isolation section. Main thoroughfare is now hot. Main thoroughfare is now hot. In accordance with regulation Zero-Zero-One-Alpha this vehicle will now be targeted for sterilization by nuclear device. Please remain calm. Your cooperation is appreciated.'

'Did you get it? The formula for the serum?' Fielding's voice was a harsh croak.

Imorkal nodded slowly. He seemed dazed. 'She is dead.'

Fielding said in a cracked whisper, 'We'll all be dead if that serum doesn't get to safe hands.'

'I am dying. More slowly than a human would but the process is inevitable.'

Fielding thought about that for all of thirty seconds. 'Get me to OpCon!' He coughed. 'Now!' Imorkal plucked him from our hands and strode off along the corridor.

OpCon was a mess of panicking technicians. Half the consoles had sprouted flowers of yellow crystal. I felt dizzy. The oxygen content of the air was shooting up. And there was a chemical stink I recognized as sulphur dioxide. Before long what happened to the rocks outside was going to happen here. As we watched a technician screamed and collapsed; bled acid out into her suit. Electrical systems blew out in a mess of sparks and smoke. Sprinklers activated immediately. The screams increased as the water mixed with sulphur compounds in the air to form acid? The stink was awful.

Fielding fought for air, told Imorkal to take him to the command console.

Panels in the low ceiling sprang open and breathing masks popped out?

Imorkal grabbed a mask each for himself and Fielding. I followed suit. The oxygen supply tasted of sulphur.

At the console, Fielding input some commands, brought the radio on line.

'Open Channel D. Authorization Fielding Zero-Zero-One-Beta. Field Command breached. Request urgent, repeat urgent, sterilization of this base and surrounding land to a radius of sixty miles by nuclear device.

Condition Black, repeat Condition Black. Agent Yellow is on the move. I say again, Agent Yellow is on the-' Fielding coughed. Blood sprayed out from behind the breathing mask. Water from the sprinklers sprayed over him. He choked back a scream, stared at Imorkal. 'You have to get the formula out.

You know that.'

Imorkal nodded.

Fielding looked at Chris and gasped, ' "Creation and destruction, all at once." It's not a virus. It's G.o.d.' He choked up the lining of his throat in a spray of blood.

Imorkal opened his third eye and looked at Fielding with absolute compa.s.sion. Fielding convulsed once and died, right there before us, in Imorkal's arms. If he'd lived another thirty seconds he would have heard a tinny voice on the radio confirm a full thermonuclear strike for thirty-one minutes' time.

Chris looked away.

Imorkal put Fielding down carefully, almost tenderly. I pulled Chris towards the airlock.

The HQ tore itself to pieces as we ran, blew apart moments after we pushed through the main airlock and into the night. For several minutes it rained bits of sulphur, bits of metal and bits of human bodies. Or what might have been human bodies. It was hard to tell. We dodged pieces of heavy machinery already blossoming with their own yellow stains. By now Imorkal was stumbling too. And Chris looked as if he'd been hit over the head with a two-by-four. At one point he half turned, stood staring as a burning jeep caught in the explosion, bounced across the road towards him. I pushed him out of the way a second before the jeep tore past in a gout of flame and yellow crystals and dissolving metal shrapnel.

Chris still wasn't going to move. 'Chris. Get up will you!' I pointed to the only chopper left on the ground. It was the one we had arrived on; parked, engine idling, a few hundred metres away beside the road. 'Chris,' I said again, urgently. 'The chopper.'

'Roz,' Chris said slowly, quietly. 'Roz, I'm sorry. I promised myself I wouldn't feel guilty. That was selfish of me. I should have known better than that?'

I punched him in the side of the face. Now was no time for guilt. We had to move or die. I told him this. He ignored me. I hit him again. Nothing. I glanced at my watch. Twenty-seven minutes to detonation.

'Chris we have to get out of here and we have to go right now!'

I was on the point of risking another punch when Chris began to move. He began to jog, then to sprint. Boy, could he move. I ran to keep up.

Then I realized: he was running towards the still-burning HQ.

I stopped. 'No, Chris, not that way! You'll - It was useless. He was gone. Oh G.o.d. Had he lost it? Gone to kill himself in some hopeless act of redemption? As if I didn't have enough to worry about!

Another explosion ripped through the vehicle.

I turned away. By the light of the fire I could see someone waving to us from the chopper. The pilot. He was waiting for us. No? He wasn't waving, he was convulsing. He fell, choking, from view. A moment later sparks flickered inside the chopper and it erupted into a ball of flame.

I think I screamed then. I certainly lost it for a while. I came to when the roar of a jeep's engine sounded beside me. Chris was sitting at the wheel.

His face was a blank mask. I thought he was going to drive straight by for a moment. Then he slammed on the brakes. I piled in. We drove on, caught up with Imorkal, and he joined us, his weight making the vehicle sag alarmingly. The jeep was already blooming with flaky yellow stains. It stank like a kid's chemistry set.

Chris drove on. I realized he was heading the wrong way again. Without bothering to speak I pushed him out of the driver's seat. The jeep slewed, but stayed level. Imorkal pulled Chris into the back seat and I took over the driver's position. I turned the jeep around and slammed it into first. Our only hope now was to drive back the way we had come. Back to our own chopper? That was going to take a while. What the h.e.l.l! We had twenty-six minutes to detonation. All the time in the world?

The jeep coughed and died five minutes later. I grabbed Chris and pulled him clear as the vehicle slumped into a ma.s.s of yellow crystals. It jerked suddenly, as the fuel system ignited. Yellow dust blew over us. I choked. I dragged Chris on up the slopes of the mountain. I suddenly stopped. Imorkal! Where was - He was right behind me, moving fast but jerkily, hissing with pain. He was tough, no doubt about it. But even he was going under. Patches of scabby yellow coated his scales? Parts of his body issued frothy yellow slime. A haze of brown gas lifted from his arms and back.

I could see the chopper up ahead now. We reached it with nineteen minutes left to detonation. My head was spinning with calculations. Time to start the engine, to lift off and attain maximum velocity. We might just get out of the killzone. If we were lucky.

We reached the chopper.

I pulled Chris towards the c.o.c.kpit. He went without protest but seemed able to make no move of his own? He certainly didn't want to climb in. He just gazed stupidly at me, like a kid who can't understand how to fix a broken toy.

'Get in!' I screamed. 'Only you can fly the d.a.m.n thing! If you don't get in we're dead!'

He didn't move.

Eighteen minutes to detonation.

'Imorkal! Help me!' The Earth Reptile moved closer, opened his third eye and looked at Chris.

Chris jerked as if electrocuted. His eyes opened wide, rolled, then settled into the familiar quiet expression I knew? 'All right, Roz. Quit riding me, I'm going.'

I shook my head at the sound of his words. He was definitely losing it. 'Get in the c.o.c.kpit! Get in, Chris! You lost it for a bit but you're OK now and we have to get out of here, right now, before the nukes go off!'

Which was due to happen in seventeen minutes. He just nodded, began to climb into the c.o.c.kpit.

He had his foot on the first step when Samran emerged from behind the fuselage. His face was half gone but his gun arm was intact, the gun, fuming from acid b.u.ms, pointing right at my head.

He smiled and the skin of his jaw slid quietly away in a runnel of blood and fumes. He was a Level Five nightmare, bleeding acid out from every visible surface, obviously terminal. I don't know how he could stand, let alone speak. But speak he did, in a very bad American accent. 'Gimme a ride, buddy?'

He began to laugh and cough blood.

His finger tightened on the gun's trigger.

Chris stepped in front of me and punched Samran hard. He did it without thinking, his fist a blur in the night. Samran's face made a noise like a bag of crisps splitting open. Chris's arm went right through his head, out and back, before I could even draw a breath.

Chris bent double with pain from the acid burns Samran's face had imparted to his fist, and Samran's first and only shot - fired more by reflex than design - went over his head.

In another moment we were in the chopper. Chris cut the preflights, goosed the engine and we took off. In less than a minute we were airborne. Ice-cold air rushed past my face. Above us umber clouds swirled, glowing yellow and brown. The Moon was up there somewhere but all I could see were the clouds, glowing with their own terrible light.

I looked down? The ground was tumbling away beneath us. A couple of miles away the wrecked HQ was burning, sending yellow and blue gouts of flame shooting upwards. I could see the reaction of Agent Yellow spreading out into the nearby rocks. They were beginning to bubble like lava, sending puffs of inflammable gases into the air. The gases caught light. The flames spread. The rock itself was burning. More yellow clouds lifted into the air.

I yelled into the night. My voice was lost in the chopper's engine noise but I didn't care. We'd made it. I'd made it. We were going to - I stopped. Suddenly I felt like throwing up. Bernice. In the panic I'd forgotten about her. G.o.d, how could I have done that? I'd left her behind!

The woman I loved, who I'd forced Chris out here at gunpoint to rescue! I'd left her behind!

I was about to mention this when I realized the chopper was descending.

What was Chris playing at? Had he frozen up again? Leaving Imorkal in the pa.s.senger section I scrambled back to the c.o.c.kpit. Chris was fine. 'We'll be landing at Dogubayazit in a few seconds?'

'For G.o.d's sake, why?'

'Because we can't leave them behind, that's why?'

I wanted to argue, to yell, to rant and beat my chest. I did none of these things because the chopper smacked into the ground at this point. Right back where it all started. Back to square one.

With eleven minutes left to live.

Dogubayazit was a ghost village, illuminated only by the sickly light of Agent Yellow, creeping steadily towards us through the rocks, through the very air I was breathing.

The village was deserted. Beside the hotel door was a puddle of organic remains about the size of a small child. A dog? A goat? I caught a glimpse of something that looked suspiciously like a Filofax caught in the mess and simply refused to think about it any more.

Pinned to the door of the hotel above the body was a note from the Doctor.

Gone to Oktemberyan. Last bus for Noah's Ark leaves tonight. Don't be late.

'Don't be late! Jesus!' '

I was running for the chopper even as I spoke, crumpled in my hand. Chris was close behind me. had been in too much pain to leave the chopper.

In another moment we were airborne again, flying east. Consulting a map he had found in the dashboard, Chris told me Oktemberyan was a small peak about six minutes' flight time away.

I looked at my watch?

Eight minutes until detonation.

Three minutes into the flight the chopper began to shake. Something was grinding hard in the engine? In the pa.s.senger compartment Imorkal was getting really sick. His skin was smoking. Pieces were starting to peel away. The process seemed to be taking longer with him - something to do with his species' DNA I suppose. I didn't care. I had all I could cope with just fighting for breath. I opened the pa.s.senger door. The wind whipped in, yanked a bunch of loose trash out into the night. Beneath us yellow light bloomed. Explosions. Thermals bounced us around like a paper model.

The air stank. I saw the ground rippling like water. Large areas where the ground simply puffed up like a bubble, then sank with a roar, emitting huge clouds of sulphur and gouts of flame. The whole area was turning into what looked like a volcano. An infectious volcano.

The chopper rocked in the updraught from a particularly devastating explosion. Imorkal reeled, emitted a thin whine. I smelt the acrid stink of dissolving metal. 'Electrical systems buried in the floor sparked and caught light. I grabbed a fire extinguisher, sprayed the exposed area of circuitry.