They walked along the beach together, the waves lapping softly near by.

On the other side of the island, another conversation was taking place.

The head of security, Magnus Payne, was standing in a large office overlooking the launch site.

Drevin was sitting on a leather sofa, reading the email that Payne had just handed him.

"Alex Rider is an MI6 agent," Payne was saying. "He may not be working for them now, but he has certainly worked for them in the past and not once but several times. If they know he is here, it is quite possible that they have already approached him and asked him to spy on you. I have searched his luggage and found nothing. But that does not mean he isn't equipped in some way."

Drevin lowered the email. "It's not possible!" His fingers began to play with his ring. "A spy? He's fourteen!"

"I agree, of course, that it is unusual." Payne's lips twisted in a sneer. "But I can a.s.sure you, Mr Drevin, that my contact is completely reliable. After what happened at the hospital, then at Hornchurch Towers and a third time at Stamford Bridge, I felt that the boy was simply too good to be true. There was something about him ... so I made enquiries." He gestured at the email. "That's the result."

"The bicycle accident?"

"In fact a bullet wound from his last a.s.signment. That's what my contact tells me."

Drevin fell silent. Payne could see his mind at work, turning over the possibilities, making evaluations. It was all there in the watery grey eyes.

"That business with the pa.s.sport in New York," he said. He snapped his fingers angrily and swore briefly in Russian. "They must have wanted to make contact with him. He was out of my sight for nearly twenty-four hours. They could have been briefing him, telling him what to do."

"They?"

"The Central Intelligence Agency." Drevin spoke the words with loathing. "They're hand in hand with MI6. The boy could be working with either of them. Or both."

"The question is, what do you want to do with him?"

"What do you suggest?"

"He's dangerous. He shouldn't be here. Not now."

"We could send him away."

"Or we could kill him."

Drevin thought for a little longer. He barely seemed to breathe. Magnus Payne waited patiently.

"You're right," Drevin said suddenly. "Paul won't be too happy about it, but that can't be helped. See to it tomorrow, Mr Payne."

He got to his feet.

"Kill him."

DEEP TROUBLE.

It was another perfect day. Alex Rider was eating breakfast with Drevin and his son on a terrace perched on the edge of the sea, the waves lapping below them. A servant all the staff had been brought in from Barbados had served them cold meat, fruit, cheese and freshly baked rolls. There was a jug of Blue Mountain coffee from Jamaica, one of the most delicious and expensive blends in the world. This was the millionaire lifestyle, all right. A stunning house, a private island, Caribbean sunshine ... a snapshot of another world.

Drevin was in an unusually good mood. It was the day before the launch and Alex could sense his excitement.

"What have you boys got planned for today?"

"Do you want to take the kite out again?" Paul asked Alex. "There might be a bit more wind."

Alex nodded. "Sure."

"Why don't you do some waterskiing?" Drevin suggested.

"We could do that too." Paul was obviously pleased that his father was taking an interest. It seemed to Alex that if Drevin had suggested a sandcastle compet.i.tion, the other boy would have agreed.

Drevin turned to Alex. "Have you ever dived?"

"Yes." Alex had been a qualified diver since he was twelve.

"Then why don't you go out this afternoon? We have all the equipment you need and you can visit the Mary Belle Mary Belle." Alex looked puzzled. Drevin went on. "It's an old transport ship; it was sunk in the Second World War while carrying supplies to the American bases in the Caribbean. Now it's an excellent dive site. You can swim into some of the holds."

Alex had been on wreck dives before. He knew that there was nothing more strangely beautiful, more eerie, than the ghost of an old ship. He turned to Paul. "Do you want to come?"

"I can't," Paul said. "My asthma..."

"Scuba is one of the many things Paul is unable to do," Drevin said. "But I can ask one of the guards to be your buddy. It would be a shame not to see it."

"Don't let me stop you, Alex," Paul added. "Everyone says the Mary Belle Mary Belle is amazing, and I've got some homework I'm supposed to do. So you go ahead." is amazing, and I've got some homework I'm supposed to do. So you go ahead."

At that moment, Tamara Knight appeared on the terrace, dressed in a linen jacket and trousers with a pair of sungla.s.ses dangling around her neck. She was carrying a bulging file.

"You've got some important correspondence to deal with, Mr Drevin," she said.

"Thank you, Miss Knight. I'll be with you in a few minutes." Drevin nodded at Alex. "Enjoy the dive," he said, and went into the house.

"You're diving?" Tamara asked. She sounded surprised.

"Yes." Alex wasn't sure what to say.

"Where?"

"The Mary Belle Mary Belle."

"Oh yes." Tamara still wasn't smiling. "You'd better be careful. I understand it's very deep. And I hope you don't see any sharks."

After breakfast, Alex went back up to his room to fetch his trunks. The shutters had been drawn back and the windows were wide open. He had a spectacular view of the whole of Little Point. Looking out, Alex saw Drevin standing by his buggy, talking into some sort of phone. Alex thought for a moment, then went over to his case and drew out the iPod Smithers had given him. He put on the headphones, turned it on, then pointed the screen in Drevin's direction. Almost at once, he heard Drevin's voice. It was so clear, he could have been standing right next to him.

"...for the final preparations. I am going over everything again today. I want all the programming to be double-checked." A pause. "The boat is coming in tonight at eleven. Not at Little Point. The western tip of the island, behind the launch site. I'll be waiting for it there..."

There was a movement at the door. It was Paul. "What are you doing, Alex?" he asked.

Alex took off the headphones. "Nothing."

Paul saw the iPod. "Are you taking that down to the beach?"

"No. I'm just checking it's working."

The two of them left together. For the rest of the morning they swam and snorkelled and went out with the kite. This time there was a little more wind and Paul taught Alex a few tricks jumps and the handle pa.s.s. But Alex found it hard to concentrate. All he could think about was the conversation he'd overheard. A boat was arriving that night at eleven. Why? Drevin obviously didn't want it to be seen. That was why he wasn't using the jetty near the house. Could it be that he was planning to leave, and, if so, should Alex alert the CIA now? No. It was too soon. Better to get over to the other side of the island once darkness had fallen and see for himself. That was the reason he was here. It would mean slipping past the checkpoint, but of course, he couldn't swim round. Alex remembered what the head of security had told him. There was razor wire concealed in the water. There had to be another way.

Lunch was at one o'clock: delicious shrimp roti served with salad and rice. Then they rested for an hour, avoiding the worst heat of the sun. At half past three there was a knock on Alex's door and a young black man appeared, wearing the grey overalls of the security staff.

"Mr Rider?" he asked.

Alex got to his feet. "I'm Alex."

"My name is Kolo. Mr Drevin said you needed a diving buddy."

"That's right."

"You a certified diver?"

"Yes."

"Then let's go!"

Paul wasn't around. Alex followed Kolo outside and down to an equipment store underneath the house. It was a large room, a cross between a garage and a boathouse. Here there was spare equipment for the various boats, a few nets and, in a separate area, scuba tanks, BCDs, wetsuits, fins and everything else needed to go diving.

"The water's warm out there," Kolo said as he hauled out a couple of tanks. "But the Mary Belle Mary Belle is deep, about twenty-two metres. So I'm going to give you a half-body wetsuit and I'll check out some weights." is deep, about twenty-two metres. So I'm going to give you a half-body wetsuit and I'll check out some weights."

Half an hour later, Alex was dressed in a bright blue neoprene wetsuit that came down to his thighs and halfway down his arms. Kolo was dressed in black. Carrying his equipment, Alex staggered out onto the beach, where a boat with a Bajan skipper was waiting to take the two of them out to sea.

"Good luck, Alex!"

Alex turned to see Paul Drevin standing on the terrace above him, waving. He waved back, then climbed into the boat.

The journey only took a few minutes. In that time, Alex went over his equipment, running through the usual checks. His mask fitted. The BCD was brand new. He turned on his air supply and checked his gauge. He had been given just under 3,000 psi. Alex made a quick calculation. The deeper he went, the more air he'd use. But he was a light breather. At twenty-two metres, the depth of the Mary Belle Mary Belle, he guessed he would have a bottom time of at least half an hour.

He noticed Kolo watching him as he finished his preparations. Alex had been looking forward to visiting the wreck, but suddenly he felt uncomfortable. He had been diving many times with his uncle and once with friends, and each time it had been a happy, sociable affair. Now he was in a boat with a captain who hadn't said a word and a buddy who had barely spoken either. Two hired hands taking the rich kid for a ride. For a moment, he understood the loneliness that Paul must have felt all his life.

The boat slowed down and the anchor was lowered. The captain raised a flag red with a white stripe signalling that there were divers in the area. Kolo helped Alex put on his equipment. Then it was time for the briefing.

"The Mary Belle Mary Belle is right underneath us," Kolo told him. "We'll enter the water over this side and then if everything's all right, we'll go straight down. The sea's a little choppy today and visibility's not so good, but you'll soon see the wreck. We'll start at the stern. You can see the rudder and propeller. Then we'll swim up the deck and into the second hold. There's plenty of fish down there. Gla.s.sfish, hatchetfish, groupers maybe you'll be lucky and see a shark. I'll signal when it's time to come back up. Any questions?" is right underneath us," Kolo told him. "We'll enter the water over this side and then if everything's all right, we'll go straight down. The sea's a little choppy today and visibility's not so good, but you'll soon see the wreck. We'll start at the stern. You can see the rudder and propeller. Then we'll swim up the deck and into the second hold. There's plenty of fish down there. Gla.s.sfish, hatchetfish, groupers maybe you'll be lucky and see a shark. I'll signal when it's time to come back up. Any questions?"

Alex shook his head.

"Then let's do it."

Alex drew his mask over his face, checked his respirator one last time, then sat on the edge of the boat with his hands crossed over his chest. Kolo gave him a thumbs up and he tipped over backwards, splashing down into the sea. It was a moment which he always enjoyed, feeling his shoulders pushing through the warm water, rolling in a coc.o.o.n of silver bubbles with the fractured light high above. Then his BCD, partly inflated, dragged him back to the surface. He was bobbing in the water, face to face with Kolo. The captain was watching them over the pulpit rail.

"All right?" Kolo shouted.

Alex gave him the universal diver's sign: finger and thumb forming an O, the other three fingers pointing up. Everything OK Everything OK.

Kolo responded with a clenched fist, thumb pointing down. Descend Descend.

Alex released the air in his BCD and let his weight belt drag him down. The water rose over his chin, past his nose and eyes. Gently he began a controlled descent, listening to the sound of his own breathing amplified in his ears. It was only now that he remembered he had been operated on just three weeks ago. What would Dr Hayward think about him scuba-diving? Well, at least it wasn't something that had been forbidden.

A triggerfish green with brilliant yellow stripes and a yellow tail swam past, taking no notice of him. The water was a deep tropical blue that became darker and murkier the further he descended. He looked at his depth gauge. Eleven metres, twelve metres, thirteen... He was comfortable, in full control. Kolo was a few metres above him, legs crossed. Great bubbles, each one containing a pearl of used air, rose in cl.u.s.ters to the surface.

And suddenly the Mary Belle Mary Belle was there, appearing in front of him as if projected onto a screen. It was always the same underwater. Objects, even ones as big as a sunken cargo ship, seemed to loom out of nowhere. Alex squeezed a little air into his BCD to slow his descent. He checked that he had neutral buoyancy, then he kicked forward and swam to examine this silent witness from the Second World War. was there, appearing in front of him as if projected onto a screen. It was always the same underwater. Objects, even ones as big as a sunken cargo ship, seemed to loom out of nowhere. Alex squeezed a little air into his BCD to slow his descent. He checked that he had neutral buoyancy, then he kicked forward and swam to examine this silent witness from the Second World War.

The Mary Belle Mary Belle lay in the sand, slanting to one side. It was in two halves, separated by a jagged, broken area that could have been made by a German torpedo. It was about a hundred and thirty metres long, twenty metres wide, the whole ship covered in algae and brightly coloured coral that would one day turn it into an extraordinary artificial reef. As he swam over the deck, heading for the stern, Alex looked down on the dark green surfaces, the twisting ladders and rails, the anchor winches and blast roof. He pa.s.sed two railway freight cars lying side by side. Part of a locomotive lay shattered, a few metres away on the sand. At the far end he saw what had to be an anti-aircraft gun, now pointing helplessly at the seabed. Once, the deck would have been full of life, with young marines running back and forth, the tannoy system barking orders, the wind and the sea spray blowing in their faces. But the lay in the sand, slanting to one side. It was in two halves, separated by a jagged, broken area that could have been made by a German torpedo. It was about a hundred and thirty metres long, twenty metres wide, the whole ship covered in algae and brightly coloured coral that would one day turn it into an extraordinary artificial reef. As he swam over the deck, heading for the stern, Alex looked down on the dark green surfaces, the twisting ladders and rails, the anchor winches and blast roof. He pa.s.sed two railway freight cars lying side by side. Part of a locomotive lay shattered, a few metres away on the sand. At the far end he saw what had to be an anti-aircraft gun, now pointing helplessly at the seabed. Once, the deck would have been full of life, with young marines running back and forth, the tannoy system barking orders, the wind and the sea spray blowing in their faces. But the Mary Belle Mary Belle had been hit. It had lain here for over half a century. There was nothing in the world more silent. It was the very definition of death. had been hit. It had lain here for over half a century. There was nothing in the world more silent. It was the very definition of death.

Alex noticed Kolo signalling to him and he swam under the stern. He had disturbed a shoal of snappers which darted away, zigzagging rapidly out of sight. The propeller was directly above him. When the ship had broken in two, the stern had turned on its side, otherwise it would have been buried in the sand. Kolo signalled again. Are you all right? Are you all right? Alex glanced at his air supply. He had used 500 psi. He signalled back. Alex glanced at his air supply. He had used 500 psi. He signalled back. Fine Fine.

Slowly they swam round the side of the wreck. Alex had his arms crossed over his chest, his hands clasping opposite arms. This was how he always dived. It helped retain body warmth and stopped him being tempted to touch anything. They rose up over the bridge and followed a ladder each rung encrusted with new life back to the upper deck. Kolo pointed at an opening beside one of the freight cars Alex had noticed. A hatchway, with a ladder leading down. It was the entrance to the second hold.

It seemed that Kolo wanted him to go in ahead of him. Alex took out his torch, then kicked down and cautiously swam through the opening, head and shoulders first. Wreck diving is entirely safe provided you know what you're doing, and Alex knew that the only real danger was getting his air pipes caught or slashing them on a sharp edge. The solution was to do everything very slowly, checking for any obstructions. But the hatch was easily wide enough for him. He followed the ladder down, turned on the torch and looked around him.

He was in a large, cavernous s.p.a.ce which ran the full width of the ship and about twenty-five metres of its length. A ghostly green light streamed in through a series of small portholes and Alex flicked off the torch, realizing he wouldn't need it. The light illuminated an array of objects instantly recognizable even after sixty years beneath the sea. There was a Jeep, parked against a wall, a stockpile of Winchester rifles, a row of boots, a pair of motorcycles. It occurred to Alex that if he had come upon these on land, they would have been rusting and ugly, nothing more than junk. But their long stay underwater had given them a strange beauty. It was as if nature was trying to claim them and magically transform them into something they had never been.

Sound is also different underwater.

Alex heard the clang of metal hitting metal but for a moment he was unsure where it had come from, or indeed what it was. He glanced left and right but nothing was moving. Then he looked back the way he'd come. There was no sign of Kolo. Why hadn't the other man swum into the hold? Then Alex realized. The hatch that he had come through had been closed. It had swung shut that was the sound he had heard.

He twisted round and swam back up the ladder. He wasn't wearing gloves and he was afraid of cutting himself, but when he reached the hatch he put his hand against it and pushed. It didn't budge. It was so securely fastened it could have been cemented into place.

What the h.e.l.l was going on? Alex felt the first stirrings of unease which could all too easily become panic. But he knew the most important rule of scuba-diving was to remain calm, and he forced himself to breathe slowly, to take everything one step at a time. The support holding back the hatch must have broken. But it didn't matter. Kolo knew he was here. There was a dive ship directly overhead. He'd just have to find another way out.

Alex backed away from the hatch and swam the length of the hold. He came to a steel wall on the other side of the truck, and although it was pitted with holes, some big enough to get an arm through, there was no way the rest of his body would be able to follow. But there was a door and it was ajar. Once it would have allowed the crew access from one hold to another. Now it was the exit that Alex needed. He swam over to it and pushed. The door opened about five centimetres but no more. It had been chained shut on the other side. Alex saw something glint. The chain was brand new. That was when he really began to worry.

A new chain on an old door. It could only be there for one reason. Somehow Drevin had found out who he was. Alex had thought he was so clever, eavesdropping with his iPod and snooping round the island. But he had let them put him on a boat and take him out to sea. He had done exactly what they wanted, swimming down into this death trap. And now they had locked the door. They were going to leave him here to drown.

Fury, black and irresistible, surged through him. His heart was thundering; he couldn't breathe. For a brief moment he was tempted to take the regulator out of his mouth and scream. He was helpless. At the mercy of a single pipe and a diminishing supply of air.

The next ninety seconds were possibly the most difficult of Alex's life. He had to fight for control, twenty-two metres below sea level, aware that he was quite probably in his tomb. Somehow he had to channel his anger away from himself, back towards Drevin, who had dealt with him as ruthlessly as anyone else who had ever crossed his path.

Another sound. An engine overhead. Alex felt a flicker of hope but quickly clamped down on it. It wasn't the sound of someone coming to rescue him. Kolo had returned to the surface. He had done his job and now he was leaving.

Sure enough, the noise faded and died away.

Alex was alone.

There was one thing he had to know, although he dreaded looking. He reached down for his instrument console. How much air had he used? The needle told him the worst. He had 1,750 psi left. At 500 psi, the gauge turned red. At that point, a spring-operated shut-off valve inside the tank's J-valve would close. He would have a few minutes left. And then he would die.

When he was sure he was back in control, he swam forward again. Alex knew that at this depth, he would soon get through what air he had left. But moving too fast, using too much energy, would only quicken the process. How long did he have? Fifteen minutes at most. Already he knew that his situation was hopeless, and he forced himself to ignore the dark whispers in his mind. n.o.body knew he was here. There was no way out. But he still had to try. Better people than Drevin had tried to kill him and failed. He was going to find a way out.

The hatch was sealed shut. The windows were too small. The floor, the ceiling and the walls were solid. There was just the single door that might lead him to safety, and that was chained. Alex looked around, then picked up one of the Winchesters. There was no chance it would fire after all these years underwater, but it might still do. Carrying the old rifle, he swam over to the door and, holding onto the stock, slid the barrel through. He would use it as a crowbar. Maybe he could prise the door open; the chain was new but it was attached to a handle that was old and might be rotten. Using all his strength, Alex pulled. Briefly he thought he could feel the metal giving. He pulled harder and jerked back as something snapped. The rifle. He had broken the barrel in half.

He swam over to the pile and picked up another. He could feel his gauges dragging behind him, but he didn't look at them again. He was too afraid of what he would see. He could hear his every breath; it echoed in his ears. And every time he opened his mouth he could see his precious air supply disappearing in a cloud of bubbles. He was hearing and seeing his own death. It was being carefully measured out all around him.

The second rifle broke just as the first had done. For a moment, Alex went mad. He grasped the door with his hands and wrenched at it as if he could tear it off its hinges. Bubbles exploded around his head. Blackness swirled around his eyes. When he calmed down, little had changed. His fingers were white, and he had cut the palm of one hand.