The air was thin in the tunnels and wisps of chlorine made their eyes water, but they continued past the walls of loosely aligned gravel and floating guidelights. The foil they rode sputtered with the lack of oxygen.
"We're not going to get through," whispered Monty. He rubbed his gloved fingers, not that it was cold, but at the thought of approaching cold if the gravel walls were breached as they sometimes did if a foil kicked up too much air.
"It'll be fine," said Janvier, his sister who was forty years younger. They shared a father, a hardscrabble miner, who went missing a decade ago. Janvier piloted the foil with calm hands on the wheels and pullgear. Her long hair floated up behind her. The cockpit of the foil was open to the air from the hole they drilled into the glass in order to steal the vehicle, and it made them vulnerable.
"Slow down," said Monty.
"Get off my back. We won't have enough fuel to--"
"No. Not enough control."
"Let me pilot--"
"No! Geez Monty. What are we gonna do, change seats right here? We'll collide with the walls for certain."
Monty was silent but seething.
"You should have let me--"
Monty shoved his hands into his armpits and slunk into his seat as much as the microgravity would allow. He found it unsatisfying.
The guidelights ahead of their path began to flicker.
"What's that?" asked Monty. "What's happening?"
"Dunno," said Janvier.
The path ahead went completely dark. Janvier pulled the brake and they stopped their forward motion. The foil hummed, it's flywheel replenished with potential energy.
"Should we use the lights?" whispered Janvier.
The plaintive wail came from within the darkness ahead.
"No," said Monty.
"Shit. You think...maybe, it's hunting us?"
"Hasn't been one in this region in years. It was blocked off."
"Maybe it was a baby--"
"Ain't no babies of that kind. When was the last turnoff?"
"Three kilometers back, but we can't go that way anyway. The passage was blocked on the last map update."
"We can't go back to the settlement."
"Shit! Was that closer? I can't tell," said Janvier.
"Get the gun."
"We could blow out the end of the tunnel!" hissed Monty.
"We can't just let it eat us! We can't just sit here!"
"So what if we kill it? There'll be more. Remember what the old miners said about them. They kept coming."
"That's bullshit meant to scare kids. They got rid of most of them. Made this a safe place to live."
"Safe place..." muttered Monty.
"Geeeeeez..." exhaled Monty. He reached down into footwell and retrieved the gun.
"Don't point that thing at me!"
"You're in the way!"
"I can't help it!"
"That's closer!" yelled Monty.
"It's a good thing they can't hear!"
This wasn't entirely true, the creatures could hear, but only at decibel levels far above human speech. More guidelights, closer, winked out. Janvier looked around at the tunnel walls.
"I have an idea..." she said.
Janvier release the brake and pressed the pullgear down an inch. She pulled tightly on the roll wheel and the foil crept closer to the right side wall, it's wings aligning themselves just above the loosest outer gravel.
"What are you doing?"
She released the roll wheel and pulled the pitch wheel slightly, adding a little thrust from the pullgear. The foil nosed into the layer of outer gravel. She put the pullgear in reverse and pulled the pitch wheel in the opposite direction and nestled further into the denser gravel. Monty felt sick.
After a few more maneuvers the foil was buried in the wall with just the cockpit exposed. Janvier shut down the engine. The guidelights just a few meters ahead went out. Both Janvier and Monty felt unable to speak being so close to the creature ahead of them. Then the guidelights in the middle of the tunnel, next to the foil went out. There was still faint light from behind them.
"It smells like iron," whispered Monty.
There was a sudden closeness. Damp. Heavy, slow lungs pushed air out of the tubercles on the sides of the creature. Brother and sister both instinctively scrunched themselves into the cockpit. The light from behind disappeared and they were left in total darkness. Something hard scraped briefly against the top of the remaining cockpit glass.
The cry was deafening and they shivered, feeling sick in their stomachs with the vibration. A humid warmth came from above--it was still passing.
"Geez, that is long," whispered Monty.
"Or slow," said Janvier.
She lifted her hand towards the break in the cockpit glass above her and pressed her fingers through. She felt a smooth presence, not skin, not metal, but warm and somehow cold at the same time. It was a being that was probably not aware of their presence, or the presence of any human invaders in its ancient home in the comet. She was glad her brother could not see what she was doing. Then there was nothing but air.
"It's past us," she whispered, withdrawing her fingers to her lap.
"How can you tell?"
"Feel it. It's not so close."
Monty ruminated, nervously chewing on the inside of his cheek.
"Give it a few more minutes," he said.
Janvier fished her penlight out of her jacket. She switched it on and shone it on her fingers. They shimmered with graphite. She rubbed the evidence off on her pants, then turned the penlight on the dashboard. The fuel level was dangerously low, but they could still make it.
"Never thought I'd be that close to one," said Monty.
"No. Me neither." Janvier switched off the penlight. They sat in the darkness for a few minutes longer and listened to the retreating wails of the creature.
"I hope there's no more."
"It's a shame," said Janvier.
"Maybe it's the last one."
"We can hope."
Janvier started the engine and turned on the headlights. They would drain energy but there was no option. She eased the foil out of the wall with the gentle touch of a curator of antiquities. When she was free she sidled to the middle of the tunnel, where the guidelights were usually strung, and accelerated.