"You can't be serious," Willard said with a vigorous shake of the head. "I'll admit that this moon is covered in life, but subterranean Europian cows...c'mon." He looked at Connelly, thinking she would immediately support his objection, but she had quickly become rigid. It was as though Robert's cow comment had set off a silent alarm inside her skull. "What's the deal with you two?"

"Kath," Robert said, as he watched the cave entrance, "Would you mind explaining the significance of a methane rich atmosphere to the boy?" Robert looked at her. "I'll watch the door."

Willard slouched. They were serious. He wondered if the stress of their near death experience had further clouded their scientific objectivity. They were setting a record for the number of times a person could jump headlong into the unknown. First detaching from TES, and then chasing a pod of Europian whales, leading them into an encounter with an alien predator and ending in this sub-oceanic cave system-which they now intended on exploring. From a safety standpoint, they were about to cross another line and Willard was beginning to consider reporting their odd behavior to Harris.

Of course, he knew the truth about Connelly's and Robert's actions. They were excited. They were scientists, analytical thinkers at heart, but what they had discovered in the past few days was nearly beyond human comprehension. What made matters worse was that every foolhardy action taken on this mission had only lead to greater discoveries that served to increase the level of excitement and, in turn, increase the number of unsafe calls. At the end of the day, if they survived, their discoveries would be hailed by science as brilliant and brave, but until then, every new wonder brought along a host of unknown dangers that Willard was beginning to resent.

No...more hate.

Ever since his own life-threatening experience in the belly of a massive predator, Willard had felt an unrelenting emotional insistence that they head back to the surface as soon as possible. More than that, he thought they should return to the Surveyor, leave orbit and make haste to Earth without looking back. But that would never happen. Not with this crew.

Willard glanced at Connelly, who had moved closer to speak to him, but had never taken her eyes off the cave entrance.

"Methane gas, as you know, is in abundance around cow farms," Connelly said. She paused and met Willard's eyes. Satisfied that he was listening, she continued. "But it's not the cow feces itself that creates the gas...it's the breakdown of organic material within the manure. This doesn't just happen with cow poop, either. You just notice it because of the high concentrations on most farms."

"Ok, fine," Willard said. "Maybe these caves are filled with methane escaping from the ocean's decomposing organisms. Fish poop, too. And don't volcanoes on Earth spew methane? It could be a naturally occurring gas here."

Willard noticed Robert pause his slow creep toward the cave entrance. "He does have a point."

Connelly nodded. "I'm sure some of the gas comes from natural sources, but the concentration of methane is high enough to suggest otherwise." Connelly switched on her PMS suit's headlamp and aimed it toward the cave. The gentle mist in the cave glowed brightly in the light. The entrance tunnel was empty. She turned to Willard again, lighting up his face. "Methane is created by the decomposition of organic material, any organic material."

"Which means that these caves could be filled with little alien rats or some kind of fungus," Willard said.

Robert looked back, shaking his head. "Nope."

"Why not?"

"Too much gas." Robert said. "The amount of organic material somewhere in this cave system must be immense, suggesting a significant population of larger creatures, probably of varying sizes, both plant and animal."

"But this cave is barren, Willard said. "There's nothing here."

Robert smiled. "You've been caving, right?"

Willard didn't want to answer. Robert knew the answer anyway. "Yeah."

"Would you say some of those caves were devoid of life?"

Willard sighed. "I came through about ten different tunnels before I made it to you two. I didn't see anything on the way."

Connelly looked at Willard with a shocked expression. "How did you find us?"

Willard sighed again. "I don't know. All I know is that we need to get the hell out of these caves and back up to the surface."

The seriousness in Willard's voice garnered him the attention of both Robert and Connelly. They stared at him, waiting for him to say more. But that's all he had. Something inside him was urging, pushing him to leave. The message was simple: run!

"You feeling okay?" Robert asked.

"I'm fi-" A shadow slid into the cave entrance. Willard blinked and the shadow slipped away.

Robert and Connelly spun towards the entrance. "What is it?" Connelly said.

"What'd you see?" Robert asked, his voice pitched higher than normal.

Conflicting emotions began vying for superiority in Willard's mind. His sense of adventure had kicked in when he saw the shadow. His interest in the unknown began to thirst for more. But he was also responsible for the welfare of Robert and Connelly. His sole job was to keep them alive. On top of all that was the persistent scream inside his brain-run!

Willard replayed the shadow in his mind. It was low to the cave floor. Short. It appeared to have limbs, how many he had no idea. But its size seemed small enough to not be a threat. But it was something. He wanted to see it, needed to see it for himself.

Willard flicked on his PMS headlamp and stepped toward the entrance. "We mark every turn so we can find our way back. I go first. If anything goes wrong, anything at all, we hightail it back to the sphere and go topside, no questions asked, no complaints." He made eye contact with both Connelly and Robert. "I am understood?"

Robert nodded.

"Perfectly," Connelly said.

Willard opened a small pack that lay with the emergency equipment and took out an ice pick.

"What's that for?" Robert asked.

He gripped the ice pick tightly and headed for the cave entrance. "I'll be damned before I let anything else swallow me today."

With every light-footed step, Connelly felt her apprehension growing. They were entering the unknown once again. She wondered if turning back might be the wise thing to do. The information they had already amassed during their short stay beneath the surface of Europa was already full of scientific curiosities and amazing new discoveries. Several return missions to Europa would no doubt be scheduled. This moon would become her home for as long as the GEC would let her stay.

Connelly found it peculiar that her goals could have changed so radically over the past months, but she couldn't deny, no matter how much she loved Earth Oceanography, that the ecosystems on and within Europa were endlessly fascinating. She rarely felt more challenged, more rewarded...more alive.

As Connelly took another step forward, she realized that the growing sensation within her belly wasn't just nervousness about facing the unknown, it was an awakening of her soul. Her mind was enraptured by her recent alien encounters and she longed for nothing else. Like a drug addict, she began to look forward to the next beast, the next fungus, the next predator, no matter how dangerous...she desired to learn everything there was to know about the organisms on this moon.

Willard stopped his forward motion with a quick jolt. Connelly stopped behind him. A swell of anxiety drowned her excitement, which now seemed irrational and foolish. She noticed Willard's grip tighten around the metal handle of the ice pick. He'd seen something.

Light cut across the cave tunnel in a wide swath as Willard peeked around a curve in the cave wall. Robert eased up behind Connelly and gently rested his hand on her shoulder. Her anxiety was eased slightly by his reassuring presence. Her breath came in controlled five second intervals as she suppressed the old feelings of uncontrollable emotions. The stale smell of her suit mixed with fresh oxygen further helped repress her rising anxiety.

I will not lose control, Connelly willed herself. I beat this a long time ago.

With a cool voice, Connelly said, "What did you see?"

Willard continued his search ten seconds more before answering. When he finally replied it was with a reticent voice. "Something's been dogging us the whole way...keeping just out of view. In the shadows."

Robert stepped forward and scanned the area with his headlamp. "I don't see anything."

"It's there," Willard said, "Just around the bend."

"What's it doing?" Robert asked.

Willard leveled his eyes plumb with Robert's. "I think it's making sure we follow it."

Robert laughed nervously. "That's, ahh, I think that's probably a bad thing..." He looked at Connelly. "Right?"

For the majority of her career Connelly had been looked at to make the final decision in different situations. The choices she made sometimes put people's lives at risk. This was the first time she wished the responsibility belonged to someone else. "I don't think we can make any judgment about the intentions of anything living down here."

Willard looked slightly annoyed. "Have we forgotten our little learning experience with the surfboard toothed Shamu?"

She took a moment to breath deep. "Ethan...what we have discovered on this moon is a complete ecosystem full of varied creatures included predators and prey. The system works here the same as it does on Earth, we just don't know which creatures are which. We could be following Europa's version of a chipmunk."

"Or an alien Kodiak bear," Willard said.

Connelly caught a sliver of motion in her periphery and jolted her headlamp toward it. She saw a blur of a creature, low to the floor, no bigger than a small dog, scurry quickly away. There was definitely something there, but with their impenetrable suits and the small stature of the creature, Connelly was positive it posed little threat. She looked at Willard. She could see it in his eyes; he'd seen it too. "Still think it's dangerous?"

"Some of the most deadly creatures on Earth are smaller than my hand," Willard said.

"You two..." Robert started. "I swear, you're like brother and sister. I'd like to venture a compromise considering that neither of you are about to agree on anything and standing around doing absolutely nothing is a waste of time and air."

Connelly couldn't help but smile. She loved it when Robert was assertive.

"We continue on-"

Willard opened his mouth to speak, but Robert continued with a louder voice. "However, at the first, and I mean first, sign of danger, I will turn tail and retreat to the sphere. If that happens, both of you will turn and follow me, no questions asked. Can we agree on this?"

Connelly nodded. She knew that she was being over eager and that Willard was being over cautious. Robert would keep them on an even keel and had no compunction over fleeing a dangerous situation. Following his lead was the best way to satiate their curiosity without getting killed in the process.

Willard stood to the side and motioned Robert to take the lead position. "By all means, after you."

Robert took an apprehensive step forward, then paused. He reached back with an open palm. Connelly's face filled with warmth as embarrassment rushed blood to her cheeks. She couldn't believe Robert was openly expressing the desire to take her hand in front of Willard. She felt foolish and slightly disappointed when Willard handed Robert the ice pick.

"Thanks," Robert said and then set off into the tunnel.

Willard followed and Connelly brought up the rear. They moved deeper into the cave system, past several different shades of stone, all streaked with ribbons of red. Connelly noted that the entire trip took them on a slight, almost indiscernible, downward slope. They were delving deep into the stone core of Europa.

Robert paused. He waved a hand back at them. "Turn off your lights." Before she could respond, Robert reached up and switched off her belt and head lamp. Willard complied as well and the cave was plunged into a momentary darkness.

Connelly's eyes quickly adjusted and she realized she could still clearly make out Willard and Robert. The cave was aglow with vibrant, ruby red light from around a bend in the tunnel. Their bright lights made seeing in the dark caves a simple task, but they also drowned out any other light sources. She wondered how far back they could have seen this light if they had had their lamps extinguished.

Robert, true to his word, sensed no danger and continued forward. Connelly felt as though they were about to exit a cave and enter a burning forest. The light flickered and moved across the wall. She couldn't imagine what the source was. When they rounded the tunnel bend and stopped at the exit, Connelly felt her chest-gripping apprehension return. She wasn't sure if what she was seeing was a dream come true or some kind of sick nightmare.

Willard leaned over to Robert without taking his eyes off the intimidating view. "Robert..." His voice was barely a whisper.

Robert's reply was a simple grunt. He wasn't diverting his view either and was too distracted to structure a sentence.

Willard leaned closer and spoke louder. "Robert...why aren't you running?"

Like a pillar of the Parthenon, Robert stood solidly still for what seemed to be ages, but in reality was closer to three seconds. Craning his head up and around, Robert looked at the cavern. It was three times the size of any sports arena Robert had ever seen. The colossal cavity's highest point, smack dab in the center of the cavern, stood at least five hundred feet above their heads.

But it wasn't the size or scope of the cavern that captured Robert's unyielding attention. Upon entering the cave, Robert's first observation had been that it was bathed in bright red light. As his eyes adjusted to the radiance, he saw the chamber with a new clarity. Covering the floor, walls and ceiling of the cavern were thousands, perhaps hundreds of thousands of blood red Europhids. But unlike the Europhids on the surface, these glowed with the brightness of fifteen watt bulbs-each and every one of them. The radiant, scarlet light filling the cavern made Robert feel as though he were standing inside an oven.

The Europhids on the floor of the cavern were spread out in patches of various sizes and shapes, creating a maze of paths leading from one side of the cave to the other. Scanning from left to right, Robert could see several black specks along the perimeter of the cave, which he assumed were more tunnels into more caverns.

His mind wandered and he began to imagine that the entire moon, surface and subterranean realms, were ruled by the Europhids. The number of individual Europhids could very well outnumber the total quantity of humans on Earth. They were a spectacular organism, completely adapted to their inhospitable environment. A sense of awe and respect crept into Robert's thoughts. He jumped and nearly loosed his bladder when a hand clapped him hard on the shoulder.

"Robert," Willard said, leaning in close. "This really would be a good time to turn back."

"Huh?" Robert looked at Willard with a confused expression. He hadn't heard a word.

Willard sighed, made an adjustment to his com system and spoke again. "Don't respond, don't react, don't do anything to hint at what I'm about to tell you."

Robert's face scrunched into a mush of befuddlement.

"I'm transmitting to you only," Willard said. "Kathy can't hear me. Don't respond verbally to anything I say. Just nod your head inside your mask without moving your body.... You're going to have to trust me."

Robert gave a slight nod.

Willard continued. "I'm pretty sure we're not safe here, but if I point out why, Kathy's only going to continue deeper into the cave system. I know this is amazing stuff, really, but we're going to die down here if we keep making poor choices. Understand?"

Robert nodded again. He trusted Willard enough to feel the first twinges of nervousness enter his stomach. Willard's covert warning meant two things. One, they really were in danger. Willard had never misdiagnosed a dangerous situation. Second, if he was keeping the reason for leaving from Kathy, he had discovered something, something exciting-and dangerous.

Moving slowly, Robert adjusted his com settings so that Connelly could no longer hear his voice. "What did you find?"

Willard glanced down at the nearest path, leading between two patches of Europhids. It was five feet wide and coated in a thin red dust. "On the path, look closely."

Robert gazed at the path and rows of indentations began to materialize out of the cavern floor. Swallowing so hard it hurt, Robert did his best to not physically react to what he was seeing.

Footprints.

The indentations had been made by tiny feet.

Lots of them.

From Robert's vantage point it looked as though the prints were created by creatures with three small toes. Possibly multiple legs. These were mobile, land dwelling creatures. What caused Robert to catch his breath was the small indentations at the tip of each toe, indicating that the creatures that created these markings were clawed...further implying that they were predatory.

"What do you want me to do?" Robert asked.

"Exactly what you said you would do."

Robert looked Willard in the eyes.

"Run," Willard said.

In that instant, Robert realized that he should have turned tail and sprinted back to the sphere already. But the cavern held an almost magical hold on him. That hold had disappeared the moment Willard pointed out the clawed footprints. Robert's muscles were already tightening in preparation for the retreat back to the sphere, but before he could actually move, Willard stopped him.

"Shit!" Willard said, looking past Robert and into the cavern. While they were speaking, Connelly had moved silently past them, hustling forward to inspect some new discovery. Willard readjusted his com and said, "Connelly, what are you doing?"

"Something on the cave floor..." Connelly said. "Some kind of animal...I think its dead."

"Robert and I think it's probably a good idea to head out now," Willard said.

Connelly continued forward, ignoring Willard. Willard and Robert locked eyes.

"Got a game plan?" Robert asked. He didn't look forward to confronting Connelly about leaving, especially now that their newly discovered feelings for each other were out in the open. But if they were in danger, and Robert believed they were, he would risk her anger to save her life.