Subterrestrial by Michael McBride Page A

that echoed away into oblivion. Martin shot him a glance and continued onward.
    He hoped the sonic digital mapping unit was working its magic and finding whatever Butler was looking for. He didn’t want to have to come back down here with the ground-penetrating radar, not that they had that kind of time. They needed to eliminate the problem in the most expeditious manner possible so they could get back to the task at hand. A tunnel connecting two continents was one thing, but an already existing network of tunnels connecting thirty-one locations around the globe? The profit potential for whoever controlled them was limitless.
    The water rippled at the farthest extent of his beam. He watched the minute waves roll toward him and break against his upper chest. A subtle current swept past his legs.
    “Did you feel that?” Sullivan whispered.
    Martin didn’t respond. They were just a little jumpy because of what they’d seen on Little Diomede. That’s why they’d gone a full five miles to the east before entering the caves. Nothing could cover that distance in such a short period of time, especially through these flooded passages. Even if their theory was right and somehow those animals had developed the ability to breathe under—
    Movement to his left.
    He’d seen something from the corner of his eye. A vague shape, barely cutting the surface.
    All that remained now was a series of ripples that died before reaching him.
    “There’s something in here with us,” Renton whispered.
    Martin shushed him, but this time didn’t look back. He focused on the water at the edge of his beam as he swept it across the surface ahead of him and drew his Heckler & Koch MK23 from the holster under his arm. It was a little heavy and unwieldy in comparison to other semiautomatic pistols, and the .45 rounds weren’t as convenient as the 9mm bullets most used, but it was corrosion-resistant and waterproof. More importantly, he knew that if he pulled the trigger, it would shoot the bullet exactly where he wanted it to go.
    He sighted the cavern down the length of his barrel and switched on the laser sight. The red dot passed from one stalactite to the next and vanished in between.
    The ground dipped underfoot and started a more severe decline. The water rose from his collarbones to his chin.
    A splash off to his right.
    He whirled and watched his light dance on the ripples, beneath which he could have sworn he saw a dark shape knife through the swirling cloud of silt.
    Another splash from behind him and Sullivan shouted.
    “Something touched my leg!”
    “I’m telling you,” Renton said. “There is definitely—”
    He disappeared under the water. The sediment billowed upward in slow motion like a mushroom cloud. An expanding wash of red diffused into the water.
    “Jesus Christ,” Sullivan said. “Did you see that? He was there. Right there. And then he was gone.”
    “Shh.”
    “He didn’t even get off a shot.”
    Martin slowly distanced himself from Sullivan. He kept his arms and legs as still as possible and did everything in his power to keep from generating ripples.
    Sullivan’s light swung wildly across the cavern. He turned in circles, swinging his pistol in front of him.
    Martin lowered his chin into the water and breathed through his nose. The barrel of his weapon barely breached the surface. He used just his toes to inch away from Sullivan as he shed his backpack and removed the fail-safes. The CL-20 charges were the most powerful nonnuclear explosives on the market and chemically stable enough to withstand the inherent geological volatility of the region. They were wired to a remote detonation system, which, when triggered, would effectively shunt this entire network of tunnels from the mainland, if not blow a hole straight through the planet.
    A shadow sliced through the water between them. The distorted shape produced a current that buffeted his legs.
    Sullivan cried out as he was jerked down. A flash and a muffled