Villanueva studied him, squinting warily. "One minute."

Linda snuggled closer to Khalid as they turned their lanterns off.

The camp was swallowed up by darkness.

It took a few seconds for Ben's eyes to adjust to the blindness, the vanquished camp lights still burning dull flares on his retinas. As these last traces faded, one area persisted, off to the left. His dilated pupils strained to focus. A glowing cave pearl. Then the glow shifted to another cave pearl. Closer. The lights were approaching. "Someone's coming," Ben said, his voice booming with relief. "They're on their way back."

Linda said, "Yes, I see it too!"

Villanueva called for lights. The darkness was beaten back by the flaring lanterns. Within minutes, bobbing flashlights could be seen approaching through the darkness. The SEAL still stood with his gun pointed forward. Once the lights were close enough, he yelled, "Stop there! Identify yourselves!"

Ashley's voice came back angrily, "Who the hell do you think it is?"

Then Michaelson's voice: "It's just us, Major. Relax."

Villanueva lowered his gun.

Ashley stomped into camp, followed by Michaelson, who kept glancing toward the river behind him. "Whose bright idea was it to turn your lights off like that?" Ashley asked sourly. "We were using them as a beacon back here. We thought something happened and started racing back. Almost ran myself right over a cliff."

Linda pointed a thumb at Ben.

"Just looking for you," he said, nodding his head toward the SEAL. "After we heard the scream, our mate here was planning on scrambling back topside with our tails between our legs if you didn't show."

Ashley bristled. "What the hell?"

Michaelson interrupted, a hand raised in the air. "He was correct. We had the radio. They didn't."

Ben swallowed. "But to leave you…"

Ashley rubbed her temples thoughtfully, then nodded. "He's right. Next time, listen to him, Ben." She brushed past him, scanning the camp. "Okay, under the circumstances, we need to make a decision whether to continue forward or go back."

Michaelson stepped forward. "I suggest Villanueva and I cross the river to take a closer look while the rest of the camp stays put."

Ashley shook her head. "No. We stick together. We've already seen what happens when we split up."

"Then we evacuate," Michaelson stated bluntly. "I won't risk any more civilians. Halloway knew the risks."

Ashley scowled. "And what if it was one of us out there screaming? Would you be so quick to leave?"

Michaelson remained silent.

"I thought so," she said. "I think Halloway deserves as much support as any of us."

Linda spoke up. "Besides, he might just be injured or unconscious. He's been silent since the first screams. We can't leave without at least looking thoroughly."

Michaelson began to object, but Ashley held up a hand. "Since it's our civilian butts on the line, it should be our decision to continue forward or not."

Ben and Linda nodded. Khalid merely stared.

"I say we go forward," Ashley said. "Any objections?"

The others remained silent.

"Fine," she said. "I want to be across that river in thirty minutes."

Ashley paced the river's edge. Villanueva had stripped to his underwear and cautiously waded into the oil-black water. A rope tied around his waist draped back to the team at the river's edge. Michaelson had anchored the rope around a stalagmite nearby.

"We could've all swum across by now," Ashley said. "All this jury-rigging is just wasting time."

"No," Michaelson said, looping a knot in the rope. "The current's too strong. If we tried to swim, someone could easily be swept away."

"Then just tie everyone together with rope." She didn't understand why he was being so obstinate. Didn't he realize every wasted second could mean Halloway's death?

Ben shook his head and tried to calm her with a smile. "Too easy to get tangled up, my dear. A good way to get someone drowned."

A loud splash drew her attention back to the river as Villanueva dove beneath the churning water, clearing half the stream before resurfacing. Strong arms cut the water in broad strokes, but still the current propelled the SEAL far downstream.

Linda grabbed Ashley's arm, pinching hard in panic. "Look!"

Ashley followed the biologist's outstretched arm back upstream from where they stood. A three-foot-tall dorsal fin, albino-white, crested the churning waters, then sank back from view.

Ben, openmouthed, had spotted it too. "Jesus Almighty Christ!"

Michaelson, with one hand tangled in the SEAL's anchoring rope, struggled to free himself, but the rope was cinched tight around his midsection. He freed his rifle and tossed it to Ben, who had the easier shot. "Use it. Before the thing reaches Villanueva."

Fumbling the rifle to his shoulder, Ben searched the water for his target. Then just below them a tip of white broke the surface, and a blast of rifle fire exploded. A small geyser of water erupted where the slug hit the water-a good several feet from the fin. Ben had missed.

"Shit," said Ben, pumping a second shell. Another miss.

Villanueva, having heard the shots over the noise of the river, had stopped and twisted around to stare at them, treading water. Linda and Ashley waved him toward the far shore. "Go! Get the hell out of there!" Ashley screamed.

The dorsal fin emerged again to its entire yard of height, now slicing the water halfway between the team and the SEAL In an arcing dive the SEAL flung his body toward the far shore, the water churned white by his pumping arms and legs. But the current resisted his progress; he seemed to be wallowing, like a fly in amber. He won't make it to shore, Ashley thought, clenching her fists, willing him strength.

The fin turned smoothly toward the thrashing SEAL.

Ben had raised the gun once more, then lowered it. "Damn it. I don't have a clear shot. At this angle, if I miss I could hit Villanueva."

Ashley snatched the rifle and raised it to her shoulder. Her first shot tore a chunk out of the fin. She aimed lower for the second shot, below the fin. As she pulled the trigger, the recoil crashed into her shoulder. This time the geyser of water from the shell's impact spurted red.

The fin tilted to the side, then sank from view.

Ashley's teeth ground together; she expected the injured creature to suddenly lurch out of the water and grind up the SEAL. She watched, the rifle butt pressed tight to her shoulder, as Villanueva reached the riverbank and scrambled up the slippery rock. He acknowledged the team's cheers with a wave and marched back upstream.

Ben stepped next to her, taking the rifle from her shaking hands. "I thought you hated guns."

She rubbed at her hands. "You've got to know something to hate it."

Ben just nodded, seeming to sense she didn't want to continue this conversation.

She stared across the river. Villanueva had untied the rope from his waist and was rigging his end to a thick stalagmite. Michaelson tugged the slack up and secured his end of the rope to a rock on this side, creating a rope bridge slung between two stalagmites. The two worked as if nothing had happened. As if some creature of nightmare hadn't just tried to swallow up one of their teammates.

The major tested the security of the bridge by tugging at it. Satisfied, he turned to the team. "Now we can cross."

Taking a deep breath, Ashley steadied her still-pounding heart. Put it behind you, she told herself. There is still a team to lead and a teammate to find.

Using carabiner hooks to attach waist harnesses to the rope, the team scooted hand over hand across the bridge. Dangling from the rope, Ashley was careful not to look down. The drop was not far, but the thought of what else might be lurking under the black reflection of water was paralyzing.