The machine unfolded and Earth fell out.

It was a sick world we were looking at.

Turkey was gone, obscured by a cloud of roiling yellow. The Sahara was gone. A lot of Asia was gone. Africa and Europe were in a bad way. The Black Sea was now princ.i.p.ally composed of acid and was enlarging its own basin, albeit very slowly, in conjunction with numerous earthquakes. The Alps were falling down; already they had lost several thousand feet.

The Earth moved around us.

Hot spots were appearing throughout the rest of the world. North America had five or six, South America between Rio de Janeiro and Buenos Aires was a mess. In Siberia there were hot spots dotted along the Urals. Tibet seemed clear, protected by the huge bulk of the Himalayas. That couldn't last. The western slopes were already on the move, shuddering groundwards in gigantic earthquakes. Only Australia seemed completely clear of infection. About that I had mixed feelings. I had never liked sheep, but kangaroos were cute.

The atmosphere writhed with Agent Yellow. Sullen nuclear suns bloomed briefly but constantly in the yellow vapour, desperate attempts to sterilize infected areas. There were places where, except for the almost familiar land ma.s.ses, I felt I was looking at an alien planet. .

n.o.body said anything? Even the sheep were quiet.

I was just glad the view wasn't detailed enough to show what was happening to the people.

The Doctor checked Jason had placed the bucket correctly in the transmission chamber, then told the Ark to upload Agent Scarlet and target the main sites of infection.

The Ark did as it was told.

I felt a fluttery sensation in my chest. Would it work? That d.a.m.n cynic inside told me everything was going too smoothly. That something was going to go wrong.

It was right, of course.

The Ark dumped Agent Scarlet into the princ.i.p.al sites of infection.

We waited. Nothing. We waited some more. Still nothing. Then again, what was I looking for? A sudden change from yellow to red indicating everything was OK? A tasty CGI effect over in a few seconds which would indicate the infection was dead, the Earth saved? I shook my head. This was a planet.

A whole planet. It might take hours, even days to see the change.

Meanwhile Agent Yellow continued to spread. The Doctor muttered, operated another set of controls, told the Ark to target other areas.

Still nothing. The villagers and soldiers stood around and watched. The animals got underfoot. Some began to complain they were hungry. Some asked where the toilet was. One asked how to pee through his force field.

Still Agent Yellow continued to spread. Another hour pa.s.sed.

'Doctor, what -?'

I placed my finger on Jason's lips. He shut up.

Finally the Doctor looked up, his boyish delight replaced by a terrible realization. 'I don't understand. It should have worked. It should have - He suddenly slumped, rubbing his eyes tiredly. 'Of course. I should have guessed. It's the bombs. The bombs they're using to try to sterilize the infected areas. The radiation is killing Agent Scarlet before it can take hold.'

He shook his head, operated a few controls, examined a few readouts.

The Earth spun around us, bringing new sites of infection into view every few seconds. 'There are a few places where Agent Scarlet is established.

But not enough to affect the broad flow of Agent Yellow. I've . . . no. I'm wrong. It's not just the radiation. It's ...

The Doctor suddenly left the console and moved towards the TARDIS. We only had to part the screens to see what it was he'd realized. The TARDIS did not look any better. If anything the infection on its outer sh.e.l.l was spreading. The Doctor stopped short, shaking his head sadly. 'It wasn't right. The formula. Something was missing. Something I missed. A codon set. Part of the viral DNA sequence. Something . . .'

Jason said quietly, 'If only we had a sample of the antivirus that Liz was working on.'

The Doctor nodded. 'Perhaps a combination of Liz's thinking and mine would produce a solution ... it always worked in the past . . .' He seemed lost in thought, a strange, half fearful look on his face. As if he had lost something precious to him. Liz? His pride?

I said, 'But we don't have Liz's formula, do we? We don't even have a sample?'

Jason bit his lip. 'Imorkal tried to put the formula into my head. I didn't get anything though. It was too - I was too scared.'

The Doctor nodded. 'The race memory. Genetic fear. It'll be centuries before Human and Earth Reptile can work together productively.' He sighed. 'This solution is not going to work. Agent Scarlet has failed. Unless we can think of something else, I'm very much afraid the Astronomer Royal is going to get his new world after all.'

I didn't quite know how to respond to that. Before I could decide, one of the villagers began to shout. Others cl.u.s.tered around him. He was beating frantically at his arm. We ran over. By the time we got there it was obvious what was happening. The infection spread to everyone by Jason had finally taken hold. True it had been slowed by the various agents Liz and the Doctor had used against it - but it was tough, it was mutating, and it was still killing.

It killed the villager as we watched; killed him slowly and painfully. It took an hour. By the time he died others were beginning to show signs of infection too. It was during the last few minutes of his death that my own skin began to itch, and then to burn. But it wasn't until I stared down at the puddle of acid sloshing around inside the man-shaped force field that I realized the Doctor's inoculations had failed.

We were all going to die.

Chapter 12.

I was watching the Doctor when the villager died. He seemed to collapse inwards as if failure had sucked the very life out of him. I felt a brief moment of pleasure - I was right and Benny was wrong: we hadn't needed him - then the feeling vanished. And to be honest I was glad. I knew that sometimes I behaved like a complete git - and that's a hard thing to admit to, let alone accept. But recently something had changed inside. I wondered if it Was the knowledge that 'I might be a parent --or the thousand years I had spent in stasis, teetering on the knife edge between madness and self understanding. Somehow being away from the situation here on the Moon, and on Earth, for so long had distanced me from it. I no longer felt driven by the immediacy of the threat. I didn't know why. Nothing had changed for the better. If anything, things were much worse. And yet I couldn't find it within myself to be involved any more. I thought back to my seemingly endless arguments with Benny. How much they had hurt. How close to the truth we might both have been and how unwilling either of us had been to acknowledge the other's point of view.

Had I become an emotional burnout, or had I grown up a bit in the last thousand years?

Now there was a question that was going to be on my mind for a while.

Longer than it would occupy the minds of those dying around me, anyway. I shot a look at Bernice. She was ignoring me. I decided to indulge her. She obviously had enough to worry about.

The Doctor looked up suddenly. He seemed to straighten imperceptibly, as if the weight of his responsibility had fallen' from him for a moment. 'Jason, tell me again what you saw in your last years on Cthalctose.'

I shrugged. He'd already heard the story once. Would telling the story again make any significant difference? 'Well, after they got the force field technology sussed, it took them a while to put it to any kind of sensible use.

They sent ships out to the region of the singularity, nosed around. They found the wreckage of the outer part of their system and a cl.u.s.ter of pinhead black holes - I think it was those that gave them the idea of restarting their Ark project, in the end.'

'They used the force fields to capture the pinhead black holes?'

'Yes. Well, two anyway. They put them in a special chamber inside the Moon and orbited them around one another. The singularities would feed off the Moon's ma.s.s, and this would provide a very long-lived source of energy for the Ark.' I looked around, wondering how many of the soldiers and villagers realized all this was my fault. 'After that, it was fairly straightforward. They designed the systems and then waited for -'

The Doctor nodded impatiently. 'Thank you, Jason.'

I shrugged. 'Glad to be of help.' If I had been of help I had no idea how.

Bernice asked the Doctor quietly: 'Are you thinking what I think you're thinking?'

Instead of answering her question, the Doctor looked at Chris. 'You remember those nuclear bombs you just disarmed?'

Chris nodded. 'Yes.'

'I want you to arm them again.' Chris blinked. 'But Roz said-'

The Doctor cut him off impatiently. 'We've no time for discussion, Chris. In a matter of ten or twelve hours Agent Yellow will have spread so far there'll be no one to save. So we've got no time to waste.'

Bernice cleared her throat. I noticed she was rubbing her arm, 'Doctor?

You are thinking what I think you're thinking, aren't you?'

The Doctor said quietly, 'EMP It's the only way.'

'The only way to what?' I asked.

'To crash the Ark's control systems and liberate the singularities.'

I felt cold. 'Destroying the Ark won't stop what's happening on Earth.'

Bernice looked at me with hollow eyes. 'That's not the point.'

Chris said, 'They'll destroy the Moon. The burst of X-rays will sterilize the Earth. Kill everything. But that'll take months to happen. We'll all be dead by then, and so will terrestrial life.'

The Doctor shook his head. 'I know a thing or two about singularities. My people learnt to use them as tools, a long time ago.'

Bernice said, 'You can't do it.'

The Doctor said, 'I can't not do it.'

Bernice scowled. 'It's cutting off your d.a.m.n nose to spite your face,' she said angrily.

The Doctor said, with terrible finality, 'It's cutting off your face to save your life.'

I said, 'Will someone please tell me what you're talking about?'

Benny said bleakly, 'He's going to liberate the singularities that power the Ark. Orbit them through the Earth. The X-ray bursts at ground level will sterilize the sites of infection.'

Even I understood that. 'But that will kill everything in the infected areas.

People. Animals. Everything.' I glanced around at the projection of the Earth. 'That's ... millions of people.'

The Doctor looked at me with infinite sadness. 'I know it's hard to accept, Jason. But it's the only way to save your world - and the billions living on it - from complete annihilation.'

There was nothing I could say to that.

Chris nodded thoughtfully and loped away towards the tunnel which led to the lunar surface.

Bernice shot me a peculiar look, then followed Chris.

I found myself thinking about that look long after the Doctor had returned, almost in a daze, to the TARDIS. What did it mean? Was she angry? Did I do something wrong again? She could hardly blame me for what had happened to the people here and on Earth. Could she?

I sighed. Suddenly I felt an overwhelming wave of depression. All around me people were dying horribly, slowly. It was my fault. Whether it was fair of Bernice to blame me or not was almost irrelevant. I sighed. I paced. I hummed and hawed. In the end there was one thing I could do. I could apologize for being such a jerkoff.

I set off up the tunnel to the surface. Only later did it occur to me to wonder when the last time I had seen Tammuz was, and where he might be now.

Ten minutes and half a mile outside the tunnel entrance I found out.

He was standing a few metres from the little trestle table holding Chris's computer and the Doctor's inverted umbrella.

Bernice was on her knees in front of Tammuz, who had one arm around her neck to immobilize her. With his other hand, Tammuz held a pistol firmly to the side of her head. I could see their force fields had melded. If Tammuz pulled the trigger now, Bernice would surely die.

I didn't know what to do. I just stood there out on the stark lunar plain, my back to a range of low hills, the Earth high and full in the sky, a sickly yellow orb. Beside me a lunar rover waited for technicians it would now never carry to and from Tranquillity Base.

Tammuz said, 'Mister Cwej. You will be so kind as to step away from the computer.'

Chris hesitated.

Bernice said, with more spirit than sense, I felt, 'If those bombs aren't armed you can kiss the Earth goodbye.'

'You think I will not recognize a lie when I hear one?' Tammuz tightened his hold on Bernice, pressing the gun against her face until she gasped. ' "I'm making a point?"' Bernice cringed as he quoted her own words right back at her. ' "Are we learning anything here today?" '

Bernice was quiet. Chris hadn't moved. I wondered if I could get around behind Tammuz, perhaps pull him off Bernice before he could fire. I didn't get the chance.

'Ah. Mister Kane. Good of you to join us. If you will be kind enough to explain to Mister Cwej why he should not destroy the stocks of weapons which the Americans obviously have hidden here I will refrain from killing your lovely wife?'

I hesitated. 'Bernice -'

She said, 'Jason, shut up. Chris. You know the score. He can't shoot you.

I'm dying anyway. The Earth has no chance if you don't arm those bombs.'

Still Chris didn't move. He seemed to be listening, but to what, I had no idea.

Bernice said, 'Jason, he's set the program, just hit -' Tammuz pushed Bernice with the barrel of his gun. Things seemed to happen with dreamlike slowness. Bernice began to fall. At the same time Chris jumped at Tammuz. Tammuz, his finger closing reflexively on the trigger of the gun, jerked away from Chris in an automatic reaction. The movement brought the gun out of Bernice's force field. The gun discharged.

Bernice fell over. Chris stopped.

For a second Tammuz didn't move. Then Bernice tangled her legs around his and he was falling. 'Jason,' she screamed, 'the computer!' Tammuz grabbed her, his hands slipping across her force field. The fields opened. I saw him groping for the emitter control strapped to her wrist. If he reached it and switched it off, or took it off her - I moved then. Faster than I would have thought possible, covering the ground in long strides.

Her voice was a scream in my ears. 'Leave me, you idiot! Get to the computer!'

She delivered a right hook to Tammuz that had him sprawling across the lunar surface. Clouds of dust rose and immediately began to settle. For a moment I lost sight of the struggling figures.

'Chris!' I yelled. 'Help her!'

Chris didn't move. Dust swirled around his feet. 'Sorry,' he said quietly, 'what was that you said, Roz?

I charged past Chris and into the cloud of lunar dust. I grabbed the first person I felt and pulled hard. It was Tammuz.

'Get your G.o.dd.a.m.n hands off my wife, don't you know she's having a baby!!!' I screamed.