There was nowhere for her to run. She dropped down beside Rubin.

'Don't shoot,' she heard Li shout. 'It's too-'

The soldier fired. He missed her. The shots thudded against the deep-sea simulator, making a gong-like sound on the glass. They ploughed straight through the oval window in a single line from left to right.

Suddenly there was an eerie silence, except for the alarm, which continued to buzz at regular intervals. They all froze and stared transfixed at the tank. Weaver heard a single loud crack. She turned her head and saw fissures spreading through the enormous sheet of glass.

'Oh, God,' groaned Rubin.

'Mick,' veiled Li. 'Get the hell over here!'

'I can't,' he whimpered, 'It's my leg. I can't move.'

'Too bad,' said Li. 'He's expendable. Let's go.'

'You can't just-' Peak was cut off before he could finish.

'Open the door, Sal.'

If Peak said anything, no one heard it. There was a deafening hang as the glass shattered. Tonnes of seawater spurted towards them. Weaver ran. Behind her a torrent of water raged through the laboratory, knocking down everything in its path.

'Karen,' she heard Rubin cry out. 'Don't leave-'

The room was full of spray. She saw Peak limping through the door, followed by Li. As the commander walked out her hand hit a switch on the wall beside the door. Weaver knew what that meant.

Li intended to lock them inside.

Water rushed up her back, pitching her forward. She crashed to her knees and scrambled up. She was drenched, but her arms were still wrapped round the case. Panting and trying not to be dragged back by the tide, she fought her way to the door as it started to close. She covered the last few metres in a single bound, glanced off the doorframe and tumbled on to the ramp.

DECK ELEVATOR

Greywolf and Anawak helped Johanson to his feet. The biologist was in a bad way, but still conscious. 'Where's Vanderbilt?' he murmured.

'Gone fishing,' said Greywolf.

Anawak felt as though he'd been run over by a train. His belly was hurting so much that he could barely keep upright.

'Jack,' he kept saying, 'Jeez, Jack.' Greywolf had saved him again. It was becoming a tradition. 'How did you get here?'

'I was a bit short with you earlier,' said Greywolf 'I wanted to apologise.'

'Are you crazy? You shouldn't be apologising for anything.'

'Thank goodness he didn't see it that way,' said Johanson, between groans.

Greywolf's face was waxen beneath the copper-coloured skin. What's wrong with him? thought Anawak. Then his friend's shoulders slumped and his eyelids fluttered…

Suddenly he noticed that Greywolf's T-shirt was covered with blood. For a moment he allowed himself to believe it was Vanderbilt's. Then he saw that the stain was growing bigger – blood was spilling from his stomach. The ship was rocked by another blast and Johanson stumbled into him. Greywolf tipped forwards and disappeared over the edge.

Jack!' Anawak dropped to his knees and slid over to where Greywolf had been standing. He was caught in one of the nets, gazing up at him. The waves crashed below. Jack, give me your hand.'

Greywolf didn't move. He stared up at Anawak, pressing his hands to his belly. Blood welled through his fingers.

Vanderbilt. The bastard had shot him.

'It's going to be OK, Jack.' Words from a movie. 'Give me your hand. I'll pull you out of there. We can do it.'

Johanson crawled to the edge. Lying flat on his belly, he tried to reach down into the net, but his arms weren't long enough.

'You need to pick yourself up,' Anawak said. Then: 'Stay there, Jack. I'm coming down. I'll push you up, and Sigur can drag you from above.'

'No,' said Greywolf.

'Jack…'

'It's better this way.'

'Don't talk like that!' Anawak snapped at him. 'I don't want to hear any of that Hollywood shit about not worrying about you and leaving you to-'

'Leon, buddy.'

'Jack! I said no!'

A thin ribbon of blood trickled out of Greywolf's mouth. 'Leon…' He smiled. All of a sudden he seemed to relax. He sat up with a jerk, rolled towards the edge of the net and splashed into the waves.

LAB

Rubin couldn't see or hear. Water from the tank swirled over him. He wondered what on earth had happened in the last few seconds. Then he felt the raging mass of water lift the shelving unit off his leg. He rose, spluttering, to the surface.

Thank God for that, he thought. At least the worst is over. The tank held a hell of a lot of water, but not enough to flood the lab. Once it had spread out, it wouldn't come higher than a metre.

Where was Li?

The body of a soldier was drifting alongside him. Another picked himself up from the water in stunned confusion.

Li was gone.

She'd abandoned them.

Rubin looked at the water, then at the door. His mind cleared. He had to get out of there. There'd been an explosion on the vessel, and they were probably sinking.

He was about to stand up, when the laboratory started to glow.

Light flashed.

It wasn't only water escaping from the tank. He tried to get up, but skidded and fell backwards. His head disappeared under water. He paddled with his hands to steady himself, and met with resistance. Something smooth. It was moving.

Lightning flashed in his eyes, then his mouth was sealed as a film of jelly spread over his face. Rubin tore at it, but his fingers kept sliding off As soon as he touched it, it morphed or dissociated. New tissue formed in its place.

This can't be happening, he thought. No!

He opened his mouth and felt the substance glide inside. He was crazy with fear. A thin feeler snaked down his throat, while other tendrils invaded his nostrils. He retched, flailing wildly and rearing up in the water. The pain was unbearable, as though instruments of torture were being inserted inside his skull. In a final moment of clarity he realised that the jelly was inside his brain.

Ever since the incident on the well deck, Rubin had been wondering whether it was strategic intention, mere curiosity or a primeval drive to crawl inside whatever looked interesting that led the yrr to explore the human brain.

Now he would wonder no more.

GREYWOLF

He felt peace. Utter calm. That probably wasn't what Vanderbilt had felt. Vanderbilt had been afraid. His death had been brutal, and rightly so, but it was different without fear.

Greywolf sank into the depths. He held his breath. Despite the terrible pain in his guts he was determined not to breathe out. Not because he thought he could lengthen his life. It was a last exertion of will-power, a final act of self-control. He would determine when the water should enter his lungs.

Licia was down there. Everything he'd ever wanted, everything he'd valued, was under water. It was only logical that he was on his way there too. It was time for him to go.

Live a good life, and one day you'll come back as an orca.

He saw a dark shadow flit through the water above him. Then another. The whales paid him no attention. That's right, thought Greywolf, I'm your friend. You won't hurt me. He knew, of course, that the real explanation was more prosaic. They hadn't noticed him. Orcas like those had no friends. They weren't even orcas any more. They had been subjugated by a species that was as ruthless as mankind.

But some day it would be OK again. The time would come. And then Greywolf would become an orca.

He breathed out.

PEAK

'Are you completely insane?' Peak's voice reverberated in the tunnel. Li sped ahead of him. He tried to ignore the throbbing in his ankle and keep pace with her. She'd abandoned the machine-gun and was carrying her pistol.