Li and Vanderbilt were sitting at a large table lit from below. The commander-in-chief stood up.

'Hello, Jude,' Johanson said cheerily. 'Nice place you've got here.'

'Sigur.' She smiled back. 'We owe you an apology.'

'Oh, don't mention it.' Johanson marvelled at his surroundings. 'I must say, I'm impressed. I guess all good things come in twos.'

'I can show you the schematics if you like.'

'I'd settle for an explanation.'

'And you shall have one.' Li did her best to look sheepish. 'But, first, let me assure you of how deeply sorry I am about the incident that led you here. Rubin should never have hit you.'

'I'm not interested in what he did. What's he doing now? What's he up to in that lab?'

'He's looking for a toxin,' said Vanderbilt.

'For a…'Johanson swallowed. 'A toxin?'

'Come on, Sigur.' Li wrung her hands. 'We couldn't rely on resolving this peacefully. I know how terrible this must sound – as if we've been operating behind your back and abusing your trust, but… well, we didn't want to push you in the wrong direction. To learn more about the yrr, it was imperative to get you working on a peaceful solution. And you've all done well. But you'd never have made such headway if we'd told you we were developing a weapon.'

'What weapon?'

'War and peace are two different ballgames. If you're working towards peace, it doesn't do to be thinking of war. Mick's exploring the alternative to peace – with the help of your research, of course.'

'He's developing a toxin to kill them?'

'Would you rather we'd commissioned you to do it?' said Vanderbilt.

'Now, look here,' said Johanson, 'our brief was to make contact. To persuade them to halt the attack. Not to destroy them.'

'You're a dreamer,' Vanderbilt said contemptuously.

'But we can do it, Jack. For God's sake, we can…'Johanson was dismayed.

'You can, can you? How?'

'We've learned so much in so little time. There's bound to be a way.'

'And if there isn't?'

'We could have discussed it together. I thought we were a team.'

'Sigur.' Li looked serious. 'There's no clear provision for what we're doing in the UN resolution. I'm well aware that we're supposed to be making contact – and that's what we're trying to do. On the other hand, I don't think we'd cause anyone much heartache if we wiped out the enemy. Don't you think it's an option we need to consider?'

Johanson stared at her. 'Well, yes – but why the charade?'

'Because high command doesn't trust you,' said Li. 'You might make a fuss. People get their ideas about scientists from the movies. They think scientists are intent on protecting and studying other life-forms, even if they turn out to be evil and dangerous…'

'The movies? The kind where the army blows up everything in sight?'

'That proves our point,' said Vanderbilt. He ran his hand over his belly.

'Please be reasonable, Sigur…'

'You're telling me that you went to all this trouble just because you thought we'd react like characters in a film?'

'No,' said Li, firmly. 'Of course not. It was a question of focusing your attention on finding out about the yrr and making contact.'

Johanson's hand swept round the room, taking in the banks of monitors.

'So why are you spying on us?'

'Rubin made a mistake that night,' Li said insistently. 'He had no right to hit you. Our surveillance systems are here for your safety. We kept the military side of the mission secret because we didn't want to unsettle the rest of the team and distract you from your work.'

'And what exactly is the purpose of our work?' Johanson was almost touching Li, staring into her eyes. 'To make peace – or be duped into providing you with all the necessary information to launch a military offensive that you've been planning from the start?'

'We had to keep both options open.'

'How far has Mick got with the military one?'

'He's had a few ideas that seem promising, but nothing concrete.' Li took a deep breath. 'I'd like to ask you in the interests of international security not to tell any of the others what you've heard. Give us time to tell them ourselves. It would be wrong to jeopardise their work when billions of people are depending on it. Soon we'll be able to cooperate as one team on both options. You've achieved the seemingly impossible – you've given our enemy a face. Once the message is ready, there'll be no more need for secrecy. And when we start working together on a weapon, we'll do so in the hope that we'll never have to-'

'Do you know what, Jude?' hissed Johanson. He was so close now that there wasn't room to pass a hand between their faces. 'I don't believe you. As soon as you've got your bloody weapons, you're going to use them. Don't you see what will happen? They're amoebas, Jude! Millions and billions of single-cell organisms. They've been around since the beginning of time. We haven't even begun to understand their role in our ecosystem. There's no way of knowing what will happen to the oceans if you kill them. There's no way of knowing what will happen to us if you kill them. But quite apart from anything else: we won't be able to stop what they've started. Are you too blinkered to see that? How do you think you're going to get the Gulf Stream flowing without the yrr? What are you going to do about the worms?'

'When we've finished with the yrr,' said Li, 'we'll start on the worms and bacteria.'

'What? You want to pick a fight with bacteria? This whole planet is made of bacteria! You can't seriously intend to exterminate microbes. Exactly how deluded are you? You might think you rule the world, but if you were to go around exterminating microbes, you'd kill this planet. You'd be the ones destroying the Earth, not the yrr. You'd wipe out all the marine life and then-'

'So darned what?' Vanderbilt erupted. 'You pathetic, ignorant, stupid, know-it-all asshole of a scientist. Who gives a toss if a few fish die, so long as we survive-'

'But we won't!' Johanson was yelling now. 'Don't you get it? Life is interconnected. And we can't fight the yrr – they're superior to us. Fighting microbes is futile. Even normal viral infections defeat us – but that's not the point. Humans only survive on this planet because Earth is ruled by microbes.'

'Sigur…' Li implored him.

He turned round. 'Open the door,' he said. 'As far as I'm concerned, this conversation is over.'

'Fine.' Li nodded, tight-lipped. 'Show Dr Johanson out, Sal.'

Peak hesitated.

'Is there something wrong with your ears, Sal? Dr Johanson has expressed his wish to leave.'

'Are you sure we can't change your mind?' said Peak, sounding helpless and strained. 'Then maybe you'd see that it is the right decision.'

'Just open the door, Sal,' said Johanson.

Peak stepped forward reluctantly and pushed a switch on the wall. The door slid open.

'And the other door, if you don't mind.'

'Of course.'

Johanson walked out.

'Sigur!'

He stopped. 'What now, Jude?'

'You've accused me of failing to see the consequences of my actions. Who knows? Perhaps you're right. But make sure you face up to the consequences of yours. If you tell the others, you'll endanger their efforts to make contact. Maybe we didn't have the right to lie to you in the first place – but you need to consider whether you've got the right to tell the truth.'

Johanson turned round slowly. Li was standing in the door of the control room. 'I'll certainly give it my careful consideration,' he said.

'Then let's strike a deal. If you hold off until I've had time to find a solution, we can talk it through this evening. And, in the meantime, neither of us will do anything that might cause problems for the other. Can you see a way of co-operating with my proposal?'