“What?” Remi asked.

“The tunnel curves back to the right. Just around the corner I can see another pier and more catwalks.”

“The plot thickens.”

CHAPTER 18

Using what remaining rope they had—sixty feet of the original seventy-five—they set up a system to ferry themselves and their gear down the right-hand tunnel. Remi went first, with Sam giving her slack from a loop around the piling until she reached the next pier.

“Okay!” she called. “It’s about thirty feet, I’d say.”

Sam reeled in the line, then attached the motor, the dinghy (which they didn’t want to leave for their pursuers to find, should they have any doubt about whether their quarry was still in the cave), the two dry bags, and the dive gear to the end. Once done, he played out the line until Remi called, “Okay, hold it.” He could hear her grunting as she fished the gear from the water. “Tied off!”

From the entrance Sam heard a gurgling sound, then the tellale sputtering blow of a regulator breaking into air. He dropped onto his belly and went still, face pressed to the pier’s planking. A flashlight clicked on and played over the walls and ceiling. In the ambient glow Sam could see the man’s head; floating beside him was a bullet-shaped object—a battery-powered sea scooter, Sam realized. Combined with good fins and strong legs, a sea scooter could propel a 180-pound man at a speed of four or five knots. So much for the outflow advantage, Sam thought.

The man threw what looked like a grappling hook over the catwalk, gave the attached rope a tug, then shouted in Russian-accented English, “All clear, come on!” The man turned the scooter toward the dock and started across the cavern.

Sam didn’t give himself a chance to think or second-guess, but gave the rope three emergency tugs, then rolled over the edge and lowered himself into the water. The current caught him and took him down the tunnel. A few seconds later the next pier came into view. Remi was kneeling on the edge, taking up the slack. Sam put his finger to his lips and she nodded and helped him onto the pier.

“Bad guys,” he whispered.

“How much time have we got?”

“Only enough to hide.”

Sam looked around. An E-shaped grid of catwalks spanned the cavern, connecting this pier to another against the opposite wall; both piers held stacks of wooden crates bearing the Kriegsmarine emblem.

Though almost twice as large as the first, this cavern was of the fracture-guided variety, which meant they would find no exit on the seaward side. Or would they? Sam thought, shining the light around. Hanging from the ceiling in the far corner was what he’d initially taken for an especially long stalactite. Under the flashlight’s beam he could now see it was actually a desiccated tangle of roots and vines drooping nearly to the water’s surface.

“A way out?” she asked.

“Maybe. The current’s slower in here.”

“Half a knot, no more,” Remi agreed.

From the first cavern they heard a pair of voices calling to one another, then a third. A gunshot echoed down the tunnel, then another, then a ten-second burst.

“Shooting into the water,” Sam whispered. “They’re trying to flush us out.”

“Look here, Sam.”

He turned the light around and pointed it at the water where she was pointing. Resting just beneath the surface was a curved shape.

“Hull,” Remi whispered.

“I think you’re right.”

“We might have just found the UM-77.”

“Come on, we got some work to do.”

Explaining his plan on the go, they wrapped the motor and the rest of their gear inside the riddled dinghy, cinched it shut using the painter line, then sank the bundle beneath the pier. Next they cut off a thirty-foot section of rope and started tying loops every few feet. Once that was done, Sam asked her, “Which part do you want?”

“You dive, I’ll climb.”

She gave him a quick kiss, then grabbed the rope and started half running, half creeping across the catwalk.

Sam took the flashlight, slipped off the pier, and dove.

He immediately realized this was not a Molch-class mini sub. It was far too small, at least six feet shorter and half the diameter of the UM-34. It was a Marder-class boat, he decided, essentially a pair of G7e torpedoes stacked atop one another, the upper one hollowed out and converted into a cockpit/battery compartment with an acrylic-glass viewing dome, the lower one a live, detachable torpedo.

Following the curve of the hull to the bottom, Sam could immediately see there was no torpedo attached, but only a cockpit tube lying on its side, the viewing dome half buried in the sand. He kicked down the length of the hull to the dome, laid the flashlight in the sand, and set to work on the unlatching bolts. They were frozen in place.

Time, Sam, time . . .

His lungs began to burn. He wrapped both hands around a bolt, braced his feet on the hull, and heaved. Nothing. Tried again. Nothing.

Through the water he heard muffled voices again, this time closer. He clicked off the flashlight, looked up, got his bearings, then kicked off the sub and swam toward the far wall. The pier’s pilings appeared in the gloom and he slipped between them and turned right, following the wall. Clearing the pier, he let himself float upward and gently break the surface.

Across the cavern and down the adjoining river tunnel he could see lights dancing off the walls—Kholkov and his men at the end of the pier; they’d be coming here next. Ten feet to Sam’s left the root/ vine tangle hung just above the surface; close up it was even larger than he’d estimated, as big around as a fifty-five-gallon drum. He sidestroked to it, dug around a moment, and found Remi’s rope. He started climbing.

A minute later and fifteen feet higher his reaching hand found Remi’s foot, which was resting in a loop. He gave it a reassuring squeeze and got a wiggle in reply. He placed his foot inside a loop, did the same with his right hand, then got comfortable.

“Luck?” she whispered.

“No. Locked up tight.”

“Now what?”

“Now we wait.”

Their wait was short.

Kholkov’s men moved fast, using generally the same ferry-rope system Sam and Remi had used to reach the second pier. Peering through the vines, Sam counted six men. One of them stalked down the pier, shining a flashlight over the crates, into the water, and down the catwalks.

“Where the hell are they?” he barked.

It was Kholkov himself, Sam realized.

“You four, flush them out!” Kholkov ordered; then he nodded at the other man and said, “You, with me!”

As Kholkov and one man searched the crates, the others lined up at the pier’s edge and started firing short, controlled bursts into the water. After nearly a minute, Kholkov called, “Cease fire, cease fire!”

“There’s something down there,” one of the men called, shining his light into the water.

Kholkov walked over, looked a few moments, then pointed to two of the men. “That’s it! Get your gear and have a look.”

The men were back in five minutes, and five minutes after that they were diving under the water.

“Search the cavern first,” Kholkov ordered them. “Make sure they’re not hiding somewhere.”

In a cloud of bubbles, the men disappeared beneath the surface. Sam watched their lights move over the bottom, under both piers, and along the walls, before finally both men resurfaced.

“Not here,” one of them reported. “There’s no place to hide.”

Sam let out the breath he’d been holding. They’d missed the sunken gear.

“Perhaps they went down the river tunnel,” the man standing beside Kholkov suggested.