'Distract us?' echoed Peak.

'Yes. The enemy is attacking on all fronts at once. Some of the attacks cause nightmare scenarios, others are more of a nuisance, but the main thing is, they succeed in keeping us busy. They're needling us, which means we don't notice what's really going on. In our eagerness to limit the damage, we're blind to the ultimate threat. We're like circus clowns, balancing a series of plates on poles. All the time we're running from one pole to the next to keep the plates spinning and stop them crashing to the ground. As soon as we've spun the last plate, we have to rush back to the first. But the number of plates exceeds our powers of juggling. We won't be able to cope with the volume of attacks. Individually, whale attacks and disappearing fish stocks wouldn't be much of a worry. But taken together, they fulfill their purpose, which is to paralyzed and overwhelm us. If the phenomena continue to spread, governments are going to lose control, other states will take advantage of the situation, and there'll be regional, maybe even international, conflicts. The trouble will get out of hand, and no one will be able to stop it. We'll undermine our own strength. International aid organisations will collapse, and medical supply networks will be overstretched. The barrage of head-on assaults serves to mask what's silently unfolding in the depths, and soon we won't have the technology, energy, know-how or even the time to prevent it.'

'Prevent what?' asked Vanderbilt, in a bored voice.

'The annihilation of mankind.'

'Excuse me?'

'Isn't it obvious? They've decided to deal with us in the same way that we deal with pests. They want to wipe us out.'

'I've heard enough of this bull.'

'Before we wipe out all the life in the sea.'

The CIA chief lumbered to his feet and pointed a trembling finger at Johanson. 'That's the biggest pile of crap I've ever heard. We summoned you here to deal with a crisis. Are you trying to tell us that those, uh, do-gooding aliens from The Abyss have come back to wag their fingers at us because we've been misbehaving?'

'The Abyss? Johanson thought for a moment. 'Oh, I see. No, I wasn't thinking of creatures like that. They were extra-terrestrials.'

'It's the same kind of crap.'

'Actually, no. In The Abyss the alien creatures come from space. The film makes them out to be a nicer version of humans. They're supposed to have a moral message. The main difference, though, is that those aliens aren't interested in toppling us from our throne at the top of terrestrial evolution, which is what any intelligent species that had developed in parallel to us and that shared our planet would want to do.'

'Dr Johanson!' Vanderbilt pulled out a handkerchief, and wiped the sweat from his forehead. 'You're not a professional snoop like me. You don't have the benefit of my experience. You've done a great job in keeping us entertained for these past fifteen minutes, but the first thing you've got to do when you're trying to get to the bottom of a mess like this is to ask yourself who gains. Who stands to gain? That's how you get on the scent. Not by poking around like-'

'No one stands to gain,' said a voice.

Vanderbilt heaved himself round.

'That's just it, Vanderbilt.' Bohrmann had risen to his feet. 'Last night Kiel finished modelling the scenarios for what's likely to happen if further continental slopes collapse.'

'I know,' Vanderbilt said brusquely. 'Tsunamis and methane. We'll have a spot of bother with the climate-'

'No,' said Bohrmann. 'Not a spot of bother. It's a death sentence. We all know what happened fifty-five million years ago, the last time enormous quantities of methane were released into the atmosphere-'

'Know? Come on, it was fifty-five million years ago.'

'We reconstructed what happened – and now we're predicting that the same thing will happen again. Tsunamis are going to hit the coastlines and wipe out coastal populations. Then the surface of the Earth will get warmer, and it will keep getting warmer until we all die out. That's everyone, Mr. Vanderbilt, including the Middle East and all your terrorists. The dissociation of the hydrate reserves in the western Pacific and off the east coast of America would be enough to kill us all.'

There was a deathly hush.

'And there'll be nothing,' said Johanson softly, looking at Vanderbilt, 'absolutely nothing you can do. You won't even know where to start. And because you've been dealing with all those whales, sharks, mussels, jellies, crabs, killer algae and invisible cable-munching monsters, you won't have had time to prepare. In fact, you won't even have been able to peek under water, because all your divers, dive robots and other gadgets will have disappeared.'

'How long will it take for the atmosphere to heat up sufficiently to pose a threat to humanity?' asked Li.

Bohrmann frowned. 'A few hundred years, I guess.'

'That's OK, then,' growled Vanderbilt.

'On the contrary,' said Johanson. 'If these creatures have launched their crusade because we're threatening their habitat, they've got to get rid of us fast. A few hundred years are nothing in the context of the history of the planet, but mankind has inflicted incredible damage in no time at all. So they've quietly decided to go one step further. They've stopped the Gulf Stream.'

Bohrmann stared at him. 'They've what?'

'It's stopped already,' Weaver spoke up. 'OK, so maybe there's still a weak current, but it's practically gone. The world had better start bracing itself for another ice age. It's going to get seriously cold within the next century. It may come sooner than that – in forty or fifty years' time, or perhaps even earlier.'

'Hang on,' Peak called. 'Methane's going to heat up the planet. We know that for a fact. The climate might shift. But how does that fit with the Gulf Stream causing an ice age? What the hell happens then? Do two catastrophes balance each other out?'

Weaver turned towards him. 'I'd say they make things worse.'

IF AT FIRST it seemed that Vanderbilt was alone in vehemently rejecting the theory, over the next hour the situation changed. The assembly split into two camps that were locked in bitter combat. Everything that had happened was rolled out and picked over again. The first anomalies. The rampaging whales. The circumstances leading to the discovery of the worms. It was like watching a rugby match, as arguments were tossed back and forth, then knocked out of play by rhetorical elbows, allowing one side to surge forwards, flanked by the opposition, then thwarted by its tricks. But behind all the manoeuvring was an impulse that Anawak recognised: some people couldn't countenance the existence of a parallel intelligence that challenged the supremacy of mankind. They didn't voice their outrage, but Anawak – versed in debates about animal intelligence – could hear it. An undercurrent of aggression entered the debate. The split caused by Johanson's theory wasn't merely scientific; it created a schism within a group of experts who were, first and foremost, people. Vanderbilt counted Rubin, Frost, Roche, Shankar and a hesitant Peak on his side, while Johanson was backed by Li, Oliviera, Fenwick, Ford, Bohrmann and Anawak. At first the intelligence agents and diplomats looked on in silence, then one by one they joined the scrum.

It was astonishing.

Johanson would never have expected it, but the professional spies, arch-conservative defence advisers and counter-terrorist experts were almost unanimously on his side. One commented, I'm a reasonable kind of guy. If I hear something that seems to make sense, I'm willing to give it the benefit of the doubt. If the alternative explanation has to be pounded into shape before it fits the mould of our experience, it seems to me that it's unlikely to be true.'