but somehow without finning. Jack suddenly realized what had happened. The tide had turned . He saw Costas drop down to the tunnel and begin to fin hard, making slow progress against the current that was suddenly racing through the lower part of the chamber from the blue hole into the bowels of the reef beyond. Jack realized that he was being propelled around the upper part of the chamber in an eddy created by the current, but he found it impossible to follow it to the point where Costas had managed to get down to the tunnel. He saw that Costas had disappeared, but his voice crackled on the intercom. ‘Jack. I’m through. There’s no way you can follow me now. The current must have increased by three knots in the last minute. It’s like a vortex in here, a twister that’s sucking the water down. But I’ve got a line I’m going to feed back into the hole for you to grab. I should be able to pull you through.’
Jack let the eddy take him to a rocky outcrop protruding above the current, now clearly visible as a turbulent stream in the water. He held the rock with one hand and reached into the current with the other, feeling his hand almost rip away. Then he saw Costas’ line snake through, a dark streak below him with a small orange buoy the size of a tennis ball at the end. It waved around violently, but it was at least three metres below the top of the current and there was no way he could reach it. He heard Costas again. ‘I always keep a buoy attached to float the line. It should come up to you.’
‘That’s a negative,’ Jack said. ‘The current’s too strong.’
‘I don’t have anything more buoyant on me.’
‘How long is this current going to last?’
The intercom crackled, the interference worse now. ‘A long time, Jack. It’s a spring tide at the moment, and it’s a high one. It’s like a bathtub emptying, and you’re somewhere down the sinkhole.’
‘You mean hours.’
There was no reply for a moment, then Costas came on clearly. ‘How’s your air?’
Jack glanced at his readout, and suddenly tensed. Five hundred p.s.i. He only had a few minutes left. ‘Bad,’ he said. ‘It was my call. I had to find the archaeology. I guess I’m paying the price.’
‘I’m coming in for you.’
‘Oh no you’re not.’
‘I’m going to find something to tie the line to out here, then tie myself off at the other end and work my way down the line through that tunnel. I should have the strength to kick out of the current long enough to grab you, and the line should be strong enough to allow both of us to use it to make our way back against the current. I’m probably going out of radio range, Jack. The interference is really bad out here. I’m going to find part of the submarine wreckage to tie on to. Hang in there.’
Jack pushed off and floated back up into the upper part of the chamber. There was no point struggling against the current. He tried to relax, to slow his breathing, to conserve his remaining air. He tried to keep calm. It was always like this in diving. Things happened quickly. One moment everything is fine, euphoric, but you take a little risk along the way, and before you know it everything has gone very badly wrong, in an instant. He was in his element underwater, but he knew it was utterly unforgiving. In a cave, one poor decision, one gamble gone wrong, and that was it. His gamble with his air had been based on Costas being beside him in case he had to buddy- breathe. But then something had happened that he should have factored into the equation. They had even talked about the current on the way down. He put it down to experience, for the next time they dived in this place.
He looked at the rock, seeing the symbols again: the Atlantis symbol that had come to mean so much in his career. The eddy had pushed him into a place of stillness in the water, like the eye of a storm, and he used his breathing to acquire perfect neutral buoyancy. He had always loved doing that, the feeling he got when he knew he had achieved total equilibrium, a sensation of utter oneness with his environment that was far better than any altered-consciousness experience he could imagine. He forgot for a moment where he was, what was happening, and just revelled in being where he had always wanted to be, underwater. Each breath, each slight exhalation was precious now, because he knew what was coming next, the greatest fear of all divers. He tested his breathing, trying a deeper breath. It was tightening. He was running out of air. He tried not to panic, to breathe like someone trapped in a prison cell, banging against the walls; he had to keep measured and calm until the final moment. He did not want to die. He felt his fingers and legs begin to tingle. He remembered something, and delved into a pocket on his leg, pulling out a small writing board with a plastic sheet and a pencil. He quickly pulled out his knife, cutting a piece off the sheet, and wrote on it, feeling his air going, realizing that his vision was tunnelling. He dropped the board and tucked the note into the sleeve of his suit, where it would be found. He began gagging and retching. His neck felt as if it were about to explode. He wanted to get his helmet off, to drown rather than suffocate, but he could no longer raise his arms. He began to sink, dropping down towards the current.
Suddenly something hit him hard, and there was a flood of air in his helmet. He breathed in, great gulping breaths, feeling his head reel, his body instantly coming back to life again. Costas was holding him tight, tying the line that was looped around his own shoulders to Jack’s, keeping it free from the backup air hose that he had plugged from his backpack into Jack’s helmet. He stared into Jack’s visor. ‘You okay?’
‘That was a bit tight.’
‘Okay. Let’s get out of here.’ Costas led up the line, his bulk providing a buffer against the current that Jack was grateful to follow, keeping close behind so that the air hose was not stretched. Inch by inch they pulled themselves back through the tunnel and towards the wrecked deck gun on the U-boat where Costas had tied the line. Ten minutes after leaving the cavern they were free of the current, which wavered in the water like a giant twister about five metres in front of the U-boat’s bow. Jack began to relax, following Costas as he made his way up the casing of the submarine towards the conning tower. ‘Okay. This is what I wanted to find.’ Costas took out a small crowbar from his kit and set to work on a low metal cover about the size of a small bed. It came away easily, revealing a folded inflatable boat that had clearly been sealed in an airtight space, looking in remarkably good condition as Costas shook it out. He fumbled around beneath it, found what he wanted and leaned back. ‘Heads up,’ he said. He pulled a cord and the boat suddenly began to inflate, then billowed up and rocketed towards the surface some twenty metres above. ‘Thought we may as well enjoy some comfort while we wait for Paul,’ Costas said.
They began to ascend towards the irregular gap in the rocks that led to the surface, steering clear of the lethal whirlpool that whipped through the opening on one side. Jack looked up, seeing sunlight streaming through. Whatever had happened to the hurricane, it must have bypassed them. A dark shape came across the hole, about ten metres from them and five metres higher. Jack stared. It was impossible. ‘Costas, we’ve got company.’
Coming towards them were two divers, Saumerre and the other man. They were both wearing primitive Nazi oxygen rebreathers. ‘Shit,’ Costas said. ‘They must have found those inside the habitat. I didn’t think to look.’ Jack looked at his depth gauge. They were still eighteen metres deep, almost twice the safe depth for pure oxygen diving. The second diver seemed sluggish, trailing behind Saumerre, almost certainly showing the effects of oxygen poisoning. But he was carrying a vicious-looking knife, and they were closing in. Jack looked at Costas.
‘The guy behind is suffering. Let’s take him out first.’
Costas removed his grapple gun from its holster and loaded a round. They were less than eight metres away now, easily within range. He aimed quickly and fired, but the metal grapple shot just to the right of the man’s legs and carried on for another few metres before dropping down, pulling the grapple line with it and catching the man’s fin. He twisted round, trying to free himself, but only entangling his leg more, pulling Costas towards him. Costas fumbled to disengage the line from the carabiner, where it was hooked to his e-suit. Jack watched as the line with the grapple dangling below began to twist round and round into the whirlpool. To his horror he realized that it was pulling the man and Costas towards the vortex as well. He pulled out his knife and grabbed Costas, who had realized what was happening and was desperately trying to fin towards the rock wall. Jack finned hard against the pull of the line, then severed it with one swipe of his knife. They both rocketed forward out of the vortex. The man was already limp in the water, unconscious from oxygen poisoning, and Jack watched him plummet with horrifying speed down the whirlpool, disappearing through the tunnel to a place from which there could be no return.
When he looked up again, he realized that Saumerre had swum through the hole and was now over the reef heading out into the open ocean. It seemed a hopeless enterprise, but there was always the possibility that Saumerre’s boat had not been apprehended and would return to pick him up. Jack and Costas were too encumbered with gear to catch up. Jack made a snap decision. They were only about eight metres deep now, so he could easily surface. The dive had been shallow enough to mean that they had not exceeded their no-stop decompression time, so they shouldn’t have to worry about the bends. He took several deep breaths, then unlocked the quick release on his backpack and his helmet, pulling the unit off and pushing it away, then reaching down to where he kept an emergency mask in a pocket on his leg, quickly putting it on and clearing it. Costas look at him in alarm, but Jack did
