“And if it sees us as food rather than as a threat, it could be hunting us at this very moment.”
Mitchell restlessly scanned the surrounding foliage for any sign of movement, although for as quickly as it had attacked, he knew that if he saw anything, it was likely already too late.
“We have to go after Duan.”
“That could be exactly what it wants us to do,” Calder said. “We have no idea which predatory model it follows. Sharks like the great white stalk their prey, waiting for their opportunity to attack. For all we know, it could have been circling us from the moment we stepped off the elevator. They wait for the right moment, then cause as much physical damage as possible and simply wait for their prey to bleed to death. Or it could be more like the broadnose sevengill shark, which lies in wait until its prey gets close enough to it before attacking.”
“That sounds marginally more attractive.”
“They’re also one of the few species of shark that hunts in groups.”
The way she said it made the goosebumps rise on the backs of his arms. Until that moment he hadn’t considered the possibility that there could be more than one.
“We know that it took a bite out of Duan before it attacked,” Mitchell said.
“We can’t afford to make any assumptions,” Calder said. “That could have been something else entirely.”
“There’s a pleasant thought.”
“If it was, we could merely be dealing with an opportunistic predator attracted to the scent of blood, in which case, we’d likely be safe from a subsequent attack. If it were the same animal, though . . .”
“We could be dealing with something like the great white shark.” He looked down at the sheer volume of blood soaking into the ground around his feet. “Either way, standing here in a puddle of it can’t possibly be our best course of action. We can’t just abandon Duan, though. Not without at least trying to help him first.”
“That could be precisely what this predator expects us to do.”
“What do you propose then? Just stand here until it comes back for us?”
“Which could be exactly what—”
“It expects us to do. I get it. You’re not being very helpful.”
“Without any sort of familiarity with its food web, I can’t begin to speculate as to its behavior. Applying the Lotka-Volterra predator-prey model—”
“You really think now’s the time for a lecture?”
“We either rationalize our way through this or we’re dead. There’s a reason this species has been able to survive down here and, in case you didn’t notice, not a whole lot of others did.”
Mitchell gestured for her to proceed, but to do so in a hurry.
Plat.
Plat-plat.
“Lotka-Volterra suggests that the size of the predator population is dictated by the size of the prey population, but considering we’ve yet to see anything larger than a crab and the rate of predation is directly proportional to the incidence of physical interaction, the traditional equations fall apart. There’s either no predation or the predator has consumed all prey species, neither of which forms a stable model. Any assumptions we make would be inherently flawed.”
Mitchell’s skin crawled. Whether real or imagined, he felt the weight of unseen eyes upon him. It was all he could do to resist the overwhelming urge to run.
“What do you propose then? The longer we stand here—”
“Our behavior needs to remain unpredictable. If there is something hunting us, then we can’t replicate the behavioral patterns of its traditional prey, whatever that might be. We need to keep it off balance, cause it to hesitate to attack.”
“Then what’s the last thing it would expect us to do?”
“The last thing any apex predator would expect.” Her eyes locked onto his. “We hunt it.”
She stared off into the forest, in the direction they’d last seen it heading. Her hands shook when she brushed aside the leaves upon which Duan’s blood had started to congeal. She cringed as she knelt in the warm mud and crawled forward through the weeds.
Mitchell turned in a circle, sweeping his light across the surrounding vegetation. The cavern walls were maybe a hundred feet away in every direction, although he could barely see them through the trees. For all he knew, they could be riddled with passages leading in hundreds of directions, or they could be smooth stone and he and Calder were trapped in a dead end, in which case they were about to find out how this animal reacted to being cornered.
“Here,” Calder whispered.
Mitchell cast one final glance around him before crouching amid the ferns and leaning over her shoulder.
Calder’s beam spotlighted a section of trampled earth. The flattened weeds and detritus were damp with blood and already attempting to stand again. The print was poorly defined and vaguely resembled the splayed hoof print of a large deer, until Calder carefully brushed aside the weeds to reveal the faint impression in the mud underneath.
“At least we know it’s not a shark,” Mitchell said.
The print looked like a fat V with sides of uneven thickness and length. It was unlike that of any animal he’d seen before.
Calder glanced up at him with an expression of confusion before crawling deeper into the brush. The backs of her hands and forearms darkened with blood transferred from the blades of grass. Whatever subsequent tracks the animal might have made were erased by what looked like the weight of Duan’s dragged body. There was no doubt as to which direction it had taken him.
Calder abruptly stood and darted off into a dense grove of trees to her left, from which they could barely see the demarcation in the foliage where a nearly imperceptible path wended through the pineapple-looking trees.
“It knows this area,” she whispered. “If there’s a place where it’s safe to settle in and consume its prey, that’s likely where it’s gone.”
Something struck Mitchell’s shoulder. He glanced to his right and saw a cricket the size of a gerbil, with a hunched back and the legs of a spider, scurry down his arm. He swatted it off and looked up to see the undersides of the leaves positively crawling with them. His body involuntarily tensed at the vision of thousands of those things raining down on him at once.
“Take off your helmet,” Calder whispered. She unbuckled hers and balanced it in the nook of a bough roughly her height. Mitchell hesitated before doing the same. It was a clever ruse, although he wasn’t the biggest fan of abandoning his light for any length of time.
“Stay close.” She started forward, but he caught her by the arm.
“I’ll take the lead.”
She started to object, but he produced a pistol from the side pouch of his backpack, and she reluctantly nodded. In the dense shadows, even he could barely tell that it was a 26.5 mm flare gun and not a snub-nosed revolver. As long as he didn’t put himself in a position of having to use it, everything would be fine. Besides, he undoubtedly had more training when it came to defensive maneuvers and extricating himself and a potential victim from danger.
“Hold onto my backpack,” he whispered, and sprinted through the forest as quietly as he could. He stayed low to the ground to keep the branches from slapping his face and slalomed between trunks. His eyes scanned the area in front of him faster than his mind could keep up. Without their headlamps, they had to navigate by the violet light, which penetrated the canopy in narrow columns that barely illuminated swatches of the ground, let alone the shadows surrounding them. The soil was bare outside the light’s reach and soft with moldering leaves, which dampened the sound of their footsteps and allowed them to increase their pace.
The trees gave way to the rear wall of the cavern so suddenly that he nearly ran right into it. He leaned against the stone and looked both ways. To his left, he saw a vast expanse of rugged uninterrupted stone, while to his right—
“Do you hear that?” Calder whispered.
He nodded. It was the same noise he’d heard earlier, only much closer now
, and loud enough that he could identify it. It was the sound of running water or, more precisely, the sound of falling water.
The orifice was easily twice his height, although from a distance it had been well concealed by a grove of enormous primitive trees. He was relieved to find them mercifully bereft of the chirruping sounds of crickets, which at least spared him the threat of them crawling all over him as he passed beneath the lower canopy and returned to the world of bare stone and darkness. He didn’t realize how well his eyes had adjusted to the weak light until it began to fade with each step.
The roar of the waterfall grew deafening. He could barely see the faint reflection of light from the falling water, like sunset from a trout’s scales. It formed a curtain in front of them through which they could no more see than hear what was on the other side. A dark shape was sprawled across the path in front of it.
“Duan!”
He ran toward where the man lay heaped at the edge of a stone precipice and slid to the ground beside him. A cold mist hung in the air. He could barely hear the thudding of his pulse in his ears over the thunder of the falls as he rolled Duan onto his back.
“Jesus,” he gasped, and scurried backward in surprise.
Duan’s abdomen had been opened from one hip to the other and his viscera spilled out onto the limestone. His wetsuit was torn and his hair was knotted with twigs and briars. Droplets of water pattered his open eyes and fell between his parted lips.
Whatever attacked him must have either been unable to pass through the waterfall with the added weight of dragging Duan, or it had attempted to conceal his body somewhere out of sight, where it would be able to come back and consume him at its leisure. Or maybe they’d interrupted its meal and even now it was in there. With them.
Mitchell pushed himself to his feet and stumbled away from the body. He looked from one side of the cave to the other, then up at the ceiling. There was nowhere for it to hide. And then it hit him.
The crickets.
He whirled to face Calder.
“We have to get out of here. Now!”
Her eyes widened in comprehension.
“It left the body as bait.”
The branches of the trees behind her shook violently. Boughs snapped. Leaves exploded from the canopy. A dark shape burst from the underbrush.
Mitchell grabbed Calder by the hand and ran in the opposite direction. Watched his shadow shrink against the wall of water. Leaped over Duan’s corpse. Raised an arm to shield his head and jumped from the stone precipice.
The waterfall drove him downward. Wrenched Calder’s hand from his grasp. He felt the familiar sensation of weightlessness as he plummeted into the fathomless darkness.
IV
Thyssen tilted his head back, raised just his mouth and nose above the surface, and gasped for air. While the passage had been considerably longer than he had hoped, there had never been a point where he considered turning back. Not when his breath grew stale and heavy in his chest and not when he found himself swimming into what at first looked like a narrow cul-de-sac. Only when he calmed his mind did he see the hole in the rock above him and the tunnel that led him up to wherever he was now. He took in a long sulfurous breath and once again immersed himself. When he breached once more, it was just high enough that he could see his surroundings.
His headlamp sliced through the darkness as he turned his head. He was in a circular pool maybe a dozen feet in diameter. It grew shallower toward the end ahead of him, where the faint ripples of his creation lapped the bare limestone. The cavern stretched away from him. It was the same width as the pool, but longer even than his beam’s reach. The walls and ceiling were coarse and striated with different strata of rocks. There were uneven sections and recesses beneath outcroppings that defied his light and created shadows of inestimable depth.
A glance at the tracking device confirmed the beacons were directly ahead of him. Just shy of fifty feet and static. Something prevented him from calling out for them. Instead, he swam silently toward the edge and crawled from the water. He knelt on the stone, motionless, save for his turning head, which projected his light into the darkness.
Droplets of condensation streaked across his beam.
Plink.
Plip.
He stood and advanced in a crouch. His light reflected off shallow puddles sparkling with minerals and the droplets forming overhead on the tips of the wet stalactites. Granite jutted from a foot-thick vein in the walls, surrounded by sparkling schist. He rolled each footfall from heel to toe so as to minimize the squelching of his diving boots.
Thyssen had seen caves like this before, in Iceland and the Canary Islands. It was a lava tube, a tunnel-like cave carved by flowing lava. This was how his father had envisioned the network of warrens running through the hollow earth. It had been his theory that since lava didn’t evaporate and instead merely changed states as a consequence of temperature, there was a stable and finite volume trapped beneath the crust at all times. He believed that its movement was caused by a combination of volcanic forces, the shifting of tectonic plates, the influence of the planet’s rotation, and the exertion of gravitational forces by other celestial bodies, which caused similar tubes to form under every continent and beneath the floors of the oceans, like blood vessels inside the human body.
While Thyssen found that theory naive for any number of reasons, he was willing to concede there was a certain amount of logic to it, if founded in layman’s science. His own theory, while still in the formative stages, revolved around the idea of magma being flung outward from the periphery of the Earth’s core by gravitational forces—like droplets of water from the blades of a pinwheel—and eroding its way through the mantle in great plumes of liquid fire, carving its way outward even as the molten mantle closed its passage behind it. The magma cooled as it neared the surface and either joined stable volcanic reservoirs or simply ran out of steam. There it formed subduction zones of depleted mantle, succumbed to its diminished inertia and the forces of gravity, and settled into the Mohorovičić discontinuity, or Moho layer—the transition zone between the mantle and the crust—where it reached homeostasis in a stable, semimolten state. What it left behind were inherently stable shafts that expanded outward through the course of time as the lava inside the turning earth sought the route of least resistance to the surface.
The beacons inched closer to the center of the monitor as he advanced. Thirty feet. Twenty-five. He should have been able to see them by now.
A splash and a gasp behind him, followed by a raucous bout of coughing. He didn’t turn around. Not when the second of them erupted from the pool, sputtering and retching, or even the third. Something wasn’t right. The monitor showed the signals were twenty feet ahead of him. Was it possible they were somehow either above or below him? They were practically right next to him, as though they were standing to either side of the tunnel, simply watching him walk straight toward—
He stopped when he smelled it.
The scent. It immediately reminded him of the cavern where they’d found the sea lions, of the stench of animals only recently killed, their blood still drying on the ground.
He heard splashing behind him as the others sloshed through the shallows and onto the smooth rock. Their voices echoed all around him, but he didn’t dare risk raising his to silence them.
Thyssen brought the monitor closer to his face so he could watch the red dots without taking his eyes from the darkness at the edge of his beam for even a second. He risked one step forward, then another.
Still the beacons didn’t move.
Slowly, he knelt, removed his backpack, and withdrew a carabiner from inside. He hurled it ahead of him and listened to it clatter off into the distance.
Neither of the beacons moved.
The others were nearly on top of him now. He glanced back, waved his arm in an effort to get their attention, and then held his finger to his lips. Their conversation ceased midsentence.
Plink.
&nbs
p; Plip.
Unlike the other backpacks, his was equipped with two additional neoprene cases. The first housed the remote detonator for the fail-safes, yet another of Butler’s redundancies, while the second case was about the size of an iPad, only thick enough to house a Smith & Wesson CS9 9mm semiautomatic pistol and a spare magazine. The Chief’s Special was a compact weapon, barely larger than his hand. It wouldn’t stop a charging rhino, but it would certainly make it think twice.
Thyssen removed the pistol, cast aside the case, and held out his hand. He hoped the others would understand and stay right where they were. He advanced in a shooter’s stance, sighting the barrel slowly from one side of the lava tube to the other.
Plink.
Plat.
The source of the dripping sound neared with every step. He detected movement at the periphery of his light and aligned the beam with—
He stopped dead in his tracks.
The wall bulged outward just ahead of him. Not the stone, but a fibrous sheath, like the one they’d removed from the recess where they found the simian remains. He pressed against it with the barrel of his pistol. The material tore and a hand flopped through the hole, its fingers curled toward the ceiling like a dead spider. Blood dripped from the gaps between them.
Plip.
Plat.
A tiny cord traced the contours of the palm and disappeared into the cuff of a sleeve. He knew right away it couldn’t have been Calder, Duan, or Mitchell; none of them had been issued a com-link like his. Only members of his team had technology like that, and last he knew all of his men were aboveground.
He backed slowly away and brought his mike to his lips.
“Speranza,” he whispered. “This is Echo One. Do you copy? Speranza. This is Echo One. I repeat: do you copy?”
V
Speranza Station
Bering Sea
Ten Miles Northwest of Wales, Alaska
65°47′ N, 169°01′ W
“Speranza!” Thyssen’s voice crackled from the speakers in the communications center. “Do you copy?”
Subterrestrial Page 14