Vanished.

Glasgow, Kentucky.

May 20, 2010.

"I can say with certainty that this is excrement, mixed with some sort of inorganic matter. It looks like the webbing of a backpack or maybe the remains of an unraveled shoelace."

They were sitting back-to-back on one of the larger boulders along the shore of the river, shining two flashlights over the pile of gunk that had almost killed Gene. It was streaked from where he had stepped in it, and the print of his boot revealed synthetic material under the black goo. Russell was leaning heavily toward it, unwilling to get closer to the shore, but apparently fascinated by it. He moved his fingers around inside, pulling out long strings and laying them out in front of them. Gene could only hear him because he was inches away from his ear, but if they had been more than a few feet apart, the river would have dominated the conversation.

"I'm cautious to assign it to any one species, but I have a feeling this is bat guano," Russell went on, raising his voice over the squalling of the water. He wiped his hands off on his shorts. "On the safe side, this could be a harmless discovery. Bats account for twenty-five percent of the entire mammal population on this planet."

"What about the unsafe side?"

"It could be evidence of not a dozen small mammals, but of one dazzlingly large reptile."

"There is no such reptile," Gene responded, delighted. "That we know of."

Russell smiled slightly. "I suppose it wouldn't hurt to take a look around, to see if we can find any other signs of bats living in this part of the cave. It wouldn't be so outrageous."

With that, they separated. Gene stayed religiously on the dry rocks, moving slowly and checking every path for signs of the excrement. He also scanned the ceiling, sometimes flinching when he found himself under a layer of sharp stalactites. He could see Russell moving around on the other side of the river chamber, his light bobbing around the rocks, but he could only hear the water roaring. He imagined that he was there for hours searching and sifting, trying to pick out signs of the people who had gone missing, or evidence of the monster that ruled these caves.

Russell came over to him when he finished investigating his end of the cavern. He followed Gene patiently for a bit, providing him with observations, and then they both started back toward the camp, their wires tugging them along.

He found Helena and John splayed out on top of their sleeping bags, looking exhausted as they munched on their dinner. Russell came in behind him and unhooked his wire, letting it snap into the middle hook. Marshall was sitting in one of the exits, nibbling on something while he picked mud from his fingernails. Everyone looked up at them.

Every hair on the back of his neck stood up.

"Where is Fox?"

Helena shrugged. "He was gone when I got back."

"I haven't seen him – he didn't hook himself up," Marshall said. He gazed down the tunnel. "I guess he'll find his own way back to us."

"I'm going to look for him," Gene said, his pulse racing. He regretted escorting Russell to the river, and spending so much time searching for a way to prove their crazy theory. It meant nothing if he lost one of his companions in this cave.

He took a spotlight from his bag and navigated the tunnels much like a baby deer trying to walk through a thorny patch of wilderness. He was slow and cautious, without a guide in the darkness, but the wire constantly tugging on his pants gave him comfort. At least he would be able to get back. He walked where he could, but he kept finding drop-offs and cliffs. He couldn't imagine Mulder losing his nerve in the face of a rickety old scaffolding, so he climbed what he could, and whispered his name into every crevice.

He found his way back to the river chamber, only this time he was further up, overlooking the water. His wire was nearly at its end, the little bundle inside running out of give, so he had to stop there. He stayed back, cautious of the edge, until he ran his flashlight over it and found his companion standing to the left, at the entrance to another tunnel.

He looked bewildered.

"Fox?" Gene called.

He jumped a little at the sound, staring at him. "I saw it, Gene."

Gene frowned. "Saw what? Come over here, get away from the edge."

"I saw the creature," he explained, coming toward him. He spoke wistfully, looking at the river. "I think I know what it is. Do you know the way back?"

"I have a wire, like you're supposed to have," Gene snapped, grabbing his arm and directing him down the path he had taken. He recoiled at the coldness of his skin. He was soaking wet and freezing. "Fox… were you in the river?"

"I saw it in the water. I followed it here. You should have seen it, Gene."

He trailed off, and Gene tried to pull him back through the tunnel. He didn't budge. "We have to get you back. You'll freeze like this. You can tell me all about it later, okay?"

"But it was a ghost, Gene!"

Gene felt a chill in his spine. Mulder stumbled away from him, toward the edge.

"No, wait!" Gene said, holding up a hand. It was all he could do. When he tried to go toward him, Mulder moved a little further away. "What are you doing? Come back here!"

"I'm going to find it," Mulder announced. He backpedaled, now dangerously close to the drop off.

"Fox!"

He was gone in a flash. He stepped backward off of the edge, and within seconds Gene heard him land in the water. He looked desperately into the current, shining his light over it, but he only got a glimpse of an arm flailing as the water whisked him away. If the fall knocked him unconscious he would drown. If by some miracle he survived the water, he would encounter the ghost he had described, and he would be killed.

Gene could not let that happen.