David Gibbins - The Crusader's gold

“The right-hand tunnel!” Costas yelled. “I can see light!”

Jack swerved his hands to the right, craning his body to follow the main flow of the current. It was no use. At the last second he pulled his hands in violently to avoid smashing into the column and they tumbled into the left-hand tunnel, a narrowing pit of darkness with smooth walls like an ice chute. Jack bounced off Costas and felt an excruciating jolt in his thigh, from his injury in the ice. For a terrifying moment he was back inside the berg. “Wrong turn,” Costas yelled. Jack clutched him, could see his face behind his visor, frantic. “This is a side channel. “The main channel was flowing up towards the surface. I saw light.”

The current in the channel began to eddy, then slowed down. Even so it was impossible to swim against, and they were being pulled down inexorably. They clawed at the walls, to no avail. Suddenly everything was distorted, hazy, something Jack had last seen in the icefjord where the freshwater runoff from the glacier had formed a layer above the seawater. The water was shimmering, oily, the change in refraction caused by salinity throwing his senses into disarray. He began to feel disorientated.

“Shit,” Costas exclaimed. “That was the halocline. We’re below sea level.”

It was as if they had passed through into another dimension, into some darker world. The calcium formations were gone now, and the view ahead was bleak, forbidding. The intense, directional beam of light seemed to narrow the shaft, increasing Jack’s unease. The tunnel was elliptical, about five metres across, but the ceiling had lowered and a deep bed of gravel rose up from the floor. They were still going down, their lights boring a hole into the darkness. “Forty metres depth,” Costas said. “The Yucatan cave systems bottom out at about fifty metres, maximum. We’ve got to be going back up soon.” Jack looked at his depth gauge. Forty-six metres. Fifty-two metres. The ceiling and the floor had almost converged, and they were wedged in now, burrowing in the gravel to make space. Then they came to a standstill in a cloud of silt. Jack aimed his headlamp into the slit ahead, a crack only inches above the gravel. It was a dead end. They were trapped.

Costas heaved himself back beside Jack, his rebreather clunking against the ceiling and his body grinding through the gravel. “Something’s not right,” he said. “We were being pulled down by a current, and that’s got to go somewhere. And this gravel pile curves down at the sides, shaped by water movement. There has to be an outlet.”

He pushed himself down the right side of the gravel pile, into a narrow channel at the bottom, and pulled himself ahead until only his fins were showing. Jack closed his eyes, then opened them again, concentrating on little things, like the shape of a fossil in the limestone a few inches from his face. He looked down again to where Costas had disappeared. He could see that the crevasse was free of silt. Swept clear by the current. Costas was right.

“Jack. Follow me.” He did as Costas instructed, digging his hands into the gravel and heaving himself down the side of the tunnel. He felt the flow of water, saw light ahead. “It goes up,” Costas said excitedly. Jack followed slowly, squeezing through a boulder choke. There was hardly any room to move, and he was reduced to wriggling, his rebreather pack clanging against the stone walls. The tunnel beyond was narrower still, like a drainage pipe, smooth and rounded where the current had worn it down but only about three feet in diameter. Jack had never been in a space so narrow. It was beyond claustrophobic. There was no way they could go back, with the current pressing against them, and any blockage in the tunnel now would seal their fate. Costas’ fins were a few feet ahead of him. Jack checked his depth gauge, remained focussed. He stared at the rock inches from his face, then at his depth gauge. Forty-one metres. Thirty-seven metres. They were ascending, slowly but surely. Then the tunnel took a sharp turn upwards and they were in a chamber, a vast space filled with shadowy forms, great columns that towered upwards like white-robed giants, beckoning them up from the underworld. Far above, Jack could see a shimmer of green, distinct from the white beams of their headlights. He closed his eyes again, a wave of relief coursing through him, his heart pounding not with fear but with exhilaration. He rose beside Costas through the chamber, the water so clear that they seemed suspended in midair like figures from some scene of apotheosis. Then they were at the top of the cavern, only ten metres beneath the surface of the water, butting up against a crack in the rock where they could see the light of dawn shining through.

It was not over yet. The crack was a narrow squeeze, barely wide enough for one of them. There was no other exit from the chamber.

“Why does this always seem to happen when I dive with you?” Costas said. “Next time let’s do some open-water diving for a change.”

“If there is a next time.” Jack looked into the black chasm yawning below, then back up into the crack. He could see foliage, the wavering forms of trees overhanging the surface of the water. His heart was still pounding, but no longer with excitement. This was a ridiculous place to die.

“We’ll have to swim for it.” Costas said. “You go first.”

“No way. You’ll have the tighter squeeze, and I can help push you through.”

Costas unstrapped his rebreather and dangled it down beside him. He pulled himself as far as he could into the fissure, about two metres above Jack, then ripped off his helmet and dropped the rig. It went plummeting past Jack, disappearing into the darkness below. Jack pulled himself behind Costas and pushed up against his legs. Nothing happened. Suddenly he felt helpless, appalled that he might watch his friend die only a few metres from the surface, holding his legs. Then Costas kicked hard and erupted upwards. Jack paused to regain his breath, unbuckled his harness and dangled it beside him, took five deep breaths and then ripped off his helmet and dropped the rig. He heaved himself up through the rock, his eyes open to the blurry haze of daylight through the water, and pulled himself through. Another kick of his fins and he surfaced in a slurry of green algae, in a small pool sheltered by fronds of undergrowth.

Costas was panting on the edge of the pool, looking like the Creature from the Black Lagoon. He wiped the slime off his face, submerged his head and shook it violently, then reared up out of the water and offered Jack a hand. “You might want to do the same. Don’t want to terrify the natives.”

After Jack was out and shaking himself off, Costas reached into the top of his wetsuit and extracted a slim metallic device, about the size of a pocket calculator. He tapped the front and pulled out an aerial, bringing the device to his ear.

“Sometimes you’re a surprising bag of tricks,” Jack panted.

“Combined GPS beacon and two-way radio,” Costas said. “All I need to do now is activate the mayday button and Ben’ll have us pinpointed. I can try to establish a radio link and talk to him when we know what the situation is.”

They had surfaced beside a rough jungle track. It was still raining, alternately drizzling and pouring. Costas activated the compass on his device and quickly took a bearing. Ten minutes later they crept up the limestone dome that covered the cenote and approached the overgrown temple. The jeep that had brought them was at the end of the track. Jack saw a boy, a local Maya, playing on the road, but he had not spotted them. They stealthily rounded the building and each took one side of the entrance, their backs flat to the wall, listening. They could hear nothing. Jack could taste the salt of his sweat joining the water on his face. He looked at Costas, nodded. They sidled into the chamber, keeping to the shadows, straining their eyes into the candlelit gloom. There was no sign of Maria or Loki. The only occupant was a man sitting with his back to them on a diving tank, cleaning a pistol. Jack gestured to Costas and returned to the entrance, vigilant. Costas crept up behind Reksnys and put his arm round his throat, clamping his mouth. The pistol dropped with a clatter. Costas drew the man close and spoke with a snarl.