Anthony Horowitz - Skeleton Key

He had to find the entrance to the cave. That was why he was here. He forced himself to ignore the colours and sights of the underwater kingdom and concentrate on the rock face. The time he had spent taking his bearings before the dive paid off now. He knew more or less where the tower at the Casa de Oro stood in relation to the boat and swam in that direction, keeping the rock wall on his left. Something long and dark flashed past high above him. Alex saw it out of the comer of his eye but by the time he had turned his head it was gone. Was there a boat on the surface? Alex went down another couple of metres, searching for the cave.

In the end, it wasn’t hard to find. The entrance was circular, like a gaping mouth. This impression was heightened when Alex swam closer and looked inside. The cave hadn’t always been underwater and over a period of time-millions of years-stalactites and stalagmites had grown, needle-sharp spears that hung down from the ceiling and protruded up from the floor. As always, Alex was unable to remember which was which. But even from a distance there was something menacing about the place. It was like looking into the open mouth of some giant, undersea monster. He could almost imagine the stalactites and stalagmites biting down, the whole thing swallowing him up.

But he had to go in. The cave wasn’t very deep and apart from the rock formations it was empty, with a wide, sandy floor. He was thankful for that. Swimming too far into an underwater cave, at sunset, on his own, really would have been madness. He could see the back wall from the entrance-and there were the first of the metal rungs! They were dark red now and covered in green slime and coral, but they were clearly man-made, disappearing up the far wall and presumably continuing all the way to the top of the Devil’s Chimney. There was no sign of Turner or Troy. Had the two agents decided to climb up after all? Should Alex try to climb after them?

Alex was about to swim forward when there was another movement just outside his field of vision. Whatever he had seen before had come back, swimming the other way. Puzzled, he looked up. And froze. He actually felt the air stop somewhere at the back of his throat. The last of the bubbles chased each other up to the surface. Alex just hung there, fighting for control. He wanted to scream. But underwater, it isn’t possible to scream.

He was looking at a great white shark, at least three metres long, circling slowly above him. The sight was so unreal, so utterly shocking, that at first Alex quite literally didn’t believe his eyes.

It had to be an illusion, some sort of trick. The very fact that it was so close to him seemed impossible. He stared at the white underbelly, the two sets of fins, the down-turned crescent mouth with its jagged, razor-sharp teeth. And there were the deadly, round eyes, as black and as evil as anything on the planet. Had they seen him yet?

Alex forced himself to breathe. His heart was pounding. Not just his heart-his whole body. He could hear his breath, as if amplified, in his head. His legs hung limp beneath him, refusing to move. He was terrified. That was the simple truth. He had never been so scared in his life.

What did he know about sharks? Was the great white going to attack him? What could he do? Desperately, Alex tried to draw on what little knowledge he had.

There were three hundred and fifty known species of shark but only very few of them were known to have attacked people. The great white-carcharodon carcharias-was definitely one of them. Not so good. But shark attacks were rare. Only about a hundred people were killed every year. More people died in car accidents. On the other hand, the waters around Cuba were notoriously dangerous. This was a single shark…

…still circling him, as if choosing its moment…

…and it might not have seen him. No. That wasn’t possible. A shark’s eyes are ten times more sensitive than a human being’s. Even in pitch darkness it can see eight metres away. And anyway, it doesn’t need eyes. It has receptors built into its snout which can detect even the tiniest electrical current. A beating heart, for example.

Alex tried to force himself to calm down. His own heart was generating minute amounts of electricity. His terror would guide the creature towards him. He had to relax!

What else? Don’t splash. Don’t make any sudden movements. Advice given to him by Ian Rider came echoing back across the years. A shark will be attracted to shiny metal objects, to brightly coloured clothes, and to fresh blood. Alex slowly turned his head. His oxygen cylinder had been painted black. His T-shirt was white. There was no blood. Was there?

He turned his hands over, examining himself. And then he saw it. Just above the wrist on his left arm. There was a small gash. He hadn’t even noticed it, but now he remembered catching his wrist on the side of the boat as he fell backwards. A tiny amount of blood, brown rather than red, twisted upwards out of the wound.

Tiny, but enough. A shark can smell one drop of blood in twenty-five gallons of water. Who had taught him that? He had forgotten, but he knew it was true. The shark had smelled him…

…and was still smelling him, slowly closing in…

The circles were getting smaller. The shark’s fins were down. Its back was arched. And it was moving in a strange, jerky pattern. The three textbook signs of an imminent attack. Alex knew that he had only seconds between life and death. Slowly, trying not to make any disturbance in the water, he reached down. The knife was still there, strapped to his leg, and he carefully unfastened it. The weapon would be tiny against the bulk of the great white and the blade would seem pathetic compared to those vicious teeth. But Alex felt better having it in his hand. It was something.

He looked around him. Apart from the cave itself, there was nowhere to hide-and the cave was useless. The mouth was too wide. If he went inside, the shark would simply follow him. And yet, if he made it to the ladder, he might be able to climb it. That would take him out of the water-up the Devil’s Chimney and onto dry land. True, he would surface in the middle of the Casa de Oro.

But no matter how bad General Sarov might be, he couldn’t be worse than the shark.

He had made his decision. Slowly, keeping the shark in his sight, he began to move towards the cave’s entrance. For a moment he thought the shark had lost interest in him. It seemed to be swimming away. But then he saw that he had been tricked. The creature turned and, as if fired from a gun, rushed through the water, heading straight for him. Alex dived down, air exploding from his lungs. There was a boulder to one side of the cave and he tried to wedge himself into a corner, putting it between himself and his attacker. It worked. The shark curved away. At that moment, Alex lunged forward with the knife. He felt his arm shudder as the blade cut into the thick hide just under the two front fins. As the shark flickered past, he saw that it was leaving a trail of what looked like brown smoke. Blood. But he knew that he had barely wounded it. He had managed a pinprick, nothing more. And he had probably angered it, making it all the more determined.

Worse, he was bleeding more himself. In his attempt to get out of the way, he had backed into the coral, which had cut his arms and legs. Alex felt no pain. That would come later. But now he really had done it. He had advertised himself: dinner, fresh and bleeding. It was a miracle that the great white hadn’t been joined by a dozen friends.

He had to get into the cave. The shark was some distance away, out to sea. The cave entrance was just a few metres away to his left. Two or three kicks and he would be in-then through the stalactites and stalagmites and onto the ladder. Could he do it in time?