The air inside the dome hissed like a wounded animal, a sound that made Lieutenant Mara Voss press her palms against the reinforced glass. Outside, the twin suns of Altair-9 cast jagged shadows across the rust-colored plains, their light bleeding through the storm clouds in streaks of amber and violet. Mara’s boots echoed against the metal floor as she moved toward the control panel, her breath shallow. The colony’s life support systems had failed three hours ago, and the temperature inside was already climbing past ninety degrees. She didn’t have time to panic.
“Status report,” she barked, her voice tight.
“Oxygen at 18 percent,” came the reply from Engineer Jax Rho, his tone flat. “Atmospheric pressure dropping. If we don’t fix the filtration unit in thirty minutes, we’ll be dead before sunset.”
Mara’s fingers flew over the console, pulling up schematics of the colony’s underbelly. The filtration system was buried deep beneath the dome, a labyrinth of pipes and vents that hadn’t been serviced in years. She’d read the reports—maintenance logs flagged as incomplete, warnings about corrosion. But no one had listened. Not until now.
“I’m going down,” she said, already strapping on her suit.
“You’re crazy,” Jax snapped. “That section’s unstable. If the vents collapse—”
“Then we’re all dead anyway.” She pulled the helmet over her head, the seal hissing as it locked into place. The suit’s HUD flickered to life, displaying a map of the colony’s infrastructure. A red line pulsed where the filtration unit was located, its signal weak but steady.
The descent was a nightmare. The tunnels stank of rust and old coolant, the walls trembling with each step. Mara’s boots scuffed against the metal as she navigated the narrow passages, her flashlight cutting through the darkness. She could hear the hum of the failing system, a low, guttural sound that made her teeth ache.
Then she saw it—a massive valve, its surface pitted and corroded. The filtration unit was jammed, its gears frozen. Mara crouched beside it, her hands shaking as she pulled out a wrench. The metal was slick with condensation, and the moment she turned the handle, a deep groan echoed through the tunnels.
“Mara!” Jax’s voice crackled in her ear. “The vents are collapsing! You need to—”
The world exploded in light and noise. A tremor rocked the tunnel, sending dust and debris raining down. Mara hit the ground, her helmet clattering against the floor. The valve had burst, releasing a cloud of toxic gas that seeped into the vents above. She coughed, her vision blurring as she struggled to her feet.
“I’m okay,” she rasped, though she wasn’t sure it was true. The suit’s oxygen levels were dropping fast. She needed to get back, to warn the others—but the tunnel was collapsing, the walls buckling under the weight of the colony’s failing systems.
Then she heard it—a sound that wasn’t part of the chaos. A soft, rhythmic pulse, like a heartbeat. It was coming from the valve, from the very core of the filtration unit. Mara froze. The sound wasn’t mechanical. It was… alive.
“Jax,” she said, her voice barely above a whisper. “There’s something down here. Something inside the system.”
No response. The comms were dead.
The pulse grew louder, vibrating through the metal around her. Mara’s hand hovered over the wrench, her mind racing. She could run, escape the collapsing tunnel and hope someone else found the solution. But the sound… it was calling to her, a whisper in the static of her thoughts.
She stepped closer to the valve, her boots crunching on shattered metal. The pulse was stronger now, almost welcoming. And then she saw it—a faint glow emanating from the core of the unit, a soft blue light that pulsed in time with the sound. It wasn’t part of the system. It was something else.
Mara reached out, her fingers brushing against the metal. The moment she touched it, a surge of heat shot up her arm, and the world went black.
When she woke, the tunnel was silent. The air was crisp, clean. The filtration unit was humming smoothly, its valves moving with precision. But the glow was gone. And so was the sound.
“Mara?” Jax’s voice crackled in her ear. “You there?”
She sat up, her body aching. “I’m here.”
“What the hell happened? The system rebooted on its own. Oxygen levels are stable. But… something’s different. The readings don’t make sense.”
Mara looked around, her eyes adjusting to the dim light. The tunnel was intact, the walls smooth and unblemished. It was as if the collapse had never happened.
“I don’t know,” she said, her voice hoarse. “But whatever I touched… it changed things.”
Jax didn’t respond.
Later, when the colony’s scientists analyzed the filtration unit, they found no signs of damage. The system had repaired itself, as if it had been waiting for something—someone—to trigger the change. But Mara couldn’t shake the feeling that she’d touched something ancient, something that had been buried beneath the colony’s foundations for longer than anyone could remember.
And somewhere, deep in the tunnels, the pulse began again.
