Regardless of his employer's desire, he wasn't leaving this cavern empty-handed.

Linda watched with mixed feelings as the others exited through the wormhole. She waffled between trepidation that the team was splitting up and relief that she was safely ensconced in a cavern secure from the predators.

She noted Khalid had already returned to studying the diamonds; he seemed fixated on the wealth around them, constantly drawn back to collecting stray fragments. Villanueva dozed nearby on his mattress.

Only she stared as Ben's light faded around a curve in the wormhole. She wondered what new discoveries they would encounter, what marvels she would miss by staying behind. A small spark of envy tried to blossom into a flame, but the horrors that could also lay ahead lessened her regret.

Glancing around the small cavern, iridescent in the lamplight, she smiled at the thought that she, Linda Furstenburg, claustrophobic extraordinaire, was happy to be trapped in a confining chamber miles below the earth's surface. Let the others discover new wonders. At least here she wouldn't be something's dinner.

She crossed to the miniature laboratory she had set up. Besides, there was plenty to research right here. She sat down and checked her figures twice, then monitored the new hyphae growth under a microscope. She pulled out a slide of the older fungus and studied it too. "My god, if that isn't a chloroplast," she muttered.

Villanueva, who had been dozing nearby, opened an eye. "Are you talking to me?"

Linda blushed. "No, sorry. It's just this mold is fascinating."

Villanueva pushed into a seated position, obviously still groggy, but bored too. "What did you find?"

"I thought at first it was a dimorphic species, two forms of the same fungus. But now I don't think so. I think they are two unique species surviving symbiotically. Each sustaining the other."

"You lost me, Doc."

"One type of mold-the one with glowing hyphae-gets its energy from hydrogen sulfide in the trace volcanic gases, but its rate of growth is too fast to attribute to the amount of gas present. Plus it wastes a lot of energy to produce the glow."

"So how come it does that?"

"That's just it! There's a second species of fungus interwoven with it. This second fungus is full of a type of chloroplast!" She pointed at the microscope slide as proof.

The SEAL shrugged. "So?"

"So the second fungus uses the glowed energy from the first, like a plant uses sunlight. It feeds on this energy and in turn not only thrives, but also produces hydrogen sulfide gas to feed its glowing counterpart."

"So each mold feeds the other."

"Exactly! But obviously there must be more to it. More energy is needed to sustain this relationship. Whether from thermal heat, or from something in the rocks here, or from decomposition, or something else. I don't know. There's so much to learn. I could spend years studying just this relationship."

Villanueva seemed to be losing interest in her revelation. "Uh-huh. I'd still rather just get out of here."

"Me too, but the fungus explains a lot."

"Like what?" Villanueva yawned.

"Like why the predators down here still have eyes. Why they camouflage so well with the rock. It was strange why creatures isolated for millennia in perpetual darkness should still have eyes and need to blend into the background. Most isolated cavern species are blind and albino due to the darkness."

"Hmmm. So what you're saying is that these creatures have been mostly hanging out in lighted areas."

"Or at least at their fringes."

"That's good to know. So anywhere there's fungus, there might be predators around."

"Exactly!"

Ashley noted two things as soon as she exited the newest wormhole. It was getting damned hotter, and the fungus grew thicker and brighter the farther they descended.

They had been traveling for half a day now, stopping only to check the radio periodically. No one ever answered their call.

"We'd better conserve our batteries while we can," Ben said. "The glow here is sufficient to see by."

He was right. When all the lights were turned off, she could see just fine. She wiped her brow. The cavern ahead was spotted with bubbling pools of steaming water, the room as hot as a sauna. It reeked of rotten eggs.

Ben offered her a sip from his canteen. "We must be approaching a hot vent of the volcano."

She nodded. "We need a way up. Soon!"

Michaelson called from yards away, "Your wish has been granted, Ashley. There's a crack over here. It's scalable and seems to climb at least a hundred yards up. This may be the break we were searching for."

Ashley hurried over to him. She would climb a sheer cliff if she could get away from this sulfurous heat. She clicked her flashlight back on and probed the way up. The fissure was craggy, with many handholds and footholds. The top extended beyond her light. Excellent.

Ben approached her side. "There's another wormhole on the south wall. It heads down again."

"Who cares? We're going this way."

Ben peered up. "I don't know," he mumbled.

"What do you mean?" She gave him a perturbed look. "This is perfect."

"We can't tell where it ends. Who says it ends in a chamber? It may just peter out."

"Ben, feel the breeze. It practically sucks you up this crack. Didn't you say that meant there were continued passages?"

"I guess so." His voice was a whisper.

She glanced at him, wondering what he balked at. Surely not the climb. It looked like a piece of cake to her. "Ben?"

He shook his head as if clearing cobwebs. "Of course, you're right. Everyone hook on your quick draws and belaying harnesses. We're going up."

Ashley stared at the Aussie. She had only known him a short time but already knew his moods. Something was bothering him. "Ben, you're the expert here…"

He fastened his rope in place and approached the rock face. "I'm fine with this. Just had this urge to…" He shook his head again. "Hell, never mind. Let's go."

She watched his left hand jitter as he gripped his first handhold.

Linda woke with a snap, her head pounding. Khalid lay on a mattress nearby, snoring loudly. It was one of his rasping snorts that had startled her. She glanced at her watch. Four hours had passed since the two had retired for a nap after lunch. She glanced at Villanueva. He too was sound asleep.

Odd. She was never one to take naps, let alone allow hours to slip by like that. She sat up and stretched. Of course, the present circumstances were unusual. After running all day yesterday from monsters, her body deserved a rest.

She stood up, and the room spun; pinpoints of light exploded across her retinas. She almost stumbled to her knees, close to blacking out. After a few wobbly seconds, the spinning stabilized. Must have stood too fast, she thought, shaking her head. Her heart pounded loudly in her ears, each beat throbbing at her temples. She reached for her canteen and took a deep swallow.

Breathing heavily, she saw something that almost made her drop her canteen. The walls! The smooth-surfaced fungus was now festooned with protruding balls of growth. As she watched, several hundred pods burst, releasing a small puff of smoky dust. Spores! In the lamplight, billowing clouds of spore dust wafted through the chamber. She watched as Khalid inhaled a stream of the smoky air.

This couldn't be healthy. She knelt by Khalid and shook his shoulder. He didn't awaken. She shook him harder. Nothing. She raised his eyelids; his pupils were dilated in the bright light, nonresponsive. Damn, the spores were acting like a drug. Anesthetizing them! She realized that if they kept inhaling the drug, an overdose pended.

The fungus was trying to kill them!

Agitated, her breathing grew ragged. Blossoms of color flared across her sight. The spores! Must remain calm. Must breathe slower. Take in less of the drug. She held her breath. Still the room began to spin again. Think, damn it!