The night was unnaturally still, as if even time had paused to hold its breath against what lurked beyond human comprehension at Observatory Hill's peak where Amelia and her team were stationed for their latest project—an array designed specifically to detect cosmic signals from distant galaxies.

"Amelia," Dr. Henry Thompson whispered over the comms unit in his lab coat, "we're picking up something... unusual."

Unusual was an understatement; it felt like a physical presence pressing against Amelia's mind as she hurried towards their control room nestled within Observatory Hill’s heart—an ancient structure that had seen countless celestial mysteries but none quite so unsettling.

"What do you mean 'unusual', Henry?" She asked, her voice barely above the hum of equipment surrounding them. "We're here to detect anomalies."

Henry looked up from his console as she entered; sweat beaded on his forehead despite the room's chill.

"It’s... not like anything we've ever seen," he stammered.

Amelia leaned over him and squinted at their screens displaying a cacophony of data. "Is it some kind of cosmic interference?"

"No, no..." Henry shook head slowly back-and-forth while rubbing his temples with trembling fingers.

"It's... organic."

Organic? Amelia frowned but before she could press further on this bizarre claim—

"Dr. Sterling!" A panicked voice crackled through their comms unit.

It was Dr. Maria Rodriguez from the lower level lab, her usually calm demeanor replaced by sheer terror that sent shivers down everyone's spines.

"What is it?" Amelia asked sharply into Henry’s mic as she rushed towards him to grab hers off his desk drawer amidst scattered papers and empty coffee cups left untouched.

"We... we found something," Maria gasped between ragged breaths. "It was in one of the samples from last night—some kind of creature, but not any species I've ever seen before."

Amelia's heart pounded against her ribcage like a trapped animal clawing for escape.

"Maria! Calm down and tell me what you mean by 'creature'!"

"I...I can't explain it," Maria sobbed. "It moved when we exposed the sample to light, Amelia—it was alive."

Alive? In an ancient cosmic specimen?

Amelia's mind raced as she tried processing this new information while simultaneously attempting not lose her grip on reality.

"Alright listen up everyone!" She barked into their shared comms channel.

Her voice echoed through every speaker in the observatory; each word punctuated by static bursts that seemed to emphasize its urgency:

"We need a full lockdown immediately! No one goes outside until we figure out what's happening here!"

A chorus of affirmatives responded, though some were laced with fear and uncertainty. Amelia didn't blame them—she felt it too.

She turned back towards Henry who was staring at his screen again.

"Henry," she said softly but firmly enough to snap him from whatever trance he'd fallen into earlier,

"What did you mean by 'organic'?"

He looked up, eyes wide with fear and disbelief. "It's... like nothing we've ever encountered before Amelia—it defies all known laws of physics."

Amelia felt a chill run down her spine as she braced herself for whatever revelation was about to come next.

"It’s not just organic," Henry continued in hushed tones, leaning closer so only their comms units picked up his words. "It's... alive and it seems aware—aware enough that I think we might be dealing with something sentient."

Sentience? In an alien organism?

Amelia swallowed hard against the lump forming at her throat.

"Can you show me?"

Henry nodded, turning back to face their screens displaying a complex web of data points pulsating rhythmically across multiple monitors. He pointed towards one particular sequence that seemed more erratic than others.

"This pattern here," he said pointing with his trembling finger,

"It's repeating every 37 seconds—exactly the same interval as our heartbeats."

Amelia stared at it, her mind struggling to comprehend what she was seeing.

"That doesn't make any sense. How could something from outer space mimic human biology?"

Henry shook head slowly back-and-forth again while rubbing his temples with trembling fingers,

"I don’t know Amelia... but whatever this thing is—it's not natural."

As if on cue, a sudden burst of static erupted through their comms units followed by Maria’s scream.

"Maria!" Henry shouted into the mic. "What happened?"

There was no response except for more screams and muffled sounds that sent chills down Amelia's spine.

"We need to get downstairs," she said urgently grabbing her flashlight from its charging dock on his desk before rushing out of control room towards stairwell leading downward.

Henry followed close behind, panting heavily as they descended into darkness. The air grew colder with each step; an eerie silence hung heavy around them save for their own ragged breaths echoing off cold stone walls lined by flickering emergency lights casting long ominous shadows across the path ahead.

"Maria!" Amelia called out again once reaching lower level lab door.

Still no response. She tried opening it but found resistance—something was blocking from other side!

Using all her strength, she pushed against metal barrier until finally giving way revealing chaos within: broken glass littered floor mixed with blood and strange viscous substance oozing slowly towards them like tendrils seeking prey; Maria lay motionless amidst carnage.

Amelia rushed inside while Henry stayed back hesitantly peering over threshold before stepping cautiously forward.

"Maria!" Amelia cried out again kneeling beside her colleague checking pulse at neck—it was faint but present. She let go of breath she hadn't realized held tightly in lungs until now, relief washing through body momentarily replacing fear.

Then something moved behind them—a wet slithering sound accompanied by heavy breathing that didn’t belong to either Henry or Amelia.

They turned around slowly towards source only for horror strike deep into their souls: a monstrous creature loomed over doorway blocking any chance of escape—its form defied description, writhing mass tentacles pulsating with sickening rhythm while eyes glowed malevolently from within darkness.

Amelia felt bile rise in throat as she stared at abomination before them. It was unlike anything humanity had ever encountered; no known species could account for such monstrosity.

"Henry," Amelia whispered, barely able to form words past lump lodged firmly back into place,

"What is that thing?"

He shook head slowly side-to-side unable speak himself staring wide-eyed at creature blocking their exit.

Suddenly one of its tentacles lashed out striking Henry across face sending him crashing against wall with sickening thud. Blood spurted from deep gash on his forehead as he slumped unconscious onto cold floor, leaving Amelia alone to confront this cosmic horror now advancing menacingly towards her—its intentions clear in those glowing orbs.

She backed away slowly until pressed firmly back into corner unable move further without stepping over Maria's prone form. Heart pounded wildly against ribcage threatening burst through flesh as fear gripped every fiber of being.

"Stay... stay the fuck way from me!" Amelia screamed defiantly despite knowing futility such words held before this creature.

It paused briefly then let out guttural laugh echoing eerily around chamber—an unholy sound that seemed to mock her very existence. Then it lunged forward, tentacles writhing wildly as they reached for prey trapped helplessly within its grasp...

Amelia woke with a start gasping desperately trying draw breath into lungs burning from lack of oxygen; she realized only then how tightly closed eyes had been clenched shut throughout ordeal.

She opened them slowly blinking away tears stinging vision revealing Henry still slumped unconscious against wall while Maria remained motionless nearby. But there was no sign whatsoever any creature having ever existed within lab—just empty space where it once stood menacingly before her mere moments ago (or so felt like).

Had she imagined entire encounter? No, impossible! The carnage surrounding them couldn't be dismissed as figment of imagination.

Amelia crawled over towards Henry checking pulse again finding steady rhythm beneath fingertips. At least he was alive despite severe head wound needing immediate medical attention.

"Henry," Amelia whispered gently shaking him awake,

"We need to get out here."

He groaned softly opening eyes slowly focusing on her face before looking around disorientated at scene unfolding.

"What... what happened?" He asked weakly trying sit up but wincing in pain from injury. "I remember something attacking us..."

Amelia nodded grimly recalling events leading upto this point.

"Yeah, it did," she said helping him stand slowly onto shaky legs,

"But whatever that thing was—it's gone now."

They made their way cautiously back upstairs towards control room where Amelia grabbed first aid kit tending Henry’s wound as best possible under circumstances. Then they both sat silently staring at screens displaying data patterns still pulsating rhythmically across monitors.

"Those readings," Akira said finally breaking silence,

"They're not random, are they?"

Amelia shook head slowly side-to-side.

"No... I don't think so."

Henry looked between them confusion etched deeply into features despite pain evident in every movement. "What aren’t you telling me?" He asked warily eyeing monitors suspiciously.

Akira turned towards him explaining situation succinctly,

"Those patterns? They're repeating at intervals matching human heartbeats—exactly like the creature we encountered downstairs."

Henry paled visibly gripping armrest tightly as realization sank in.

"So whatever attacked us... it's still here?"

Amelia nodded solemnly confirming his fears. "And I think," she added grimacing,

"It might be inside one of our own people."

Amelia woke with a start, her heart pounding like it wanted to escape its ribcage confines as she found herself back in Observatory Hill's control room—Henry slumped unconscious beside Maria who still lay motionless on lab floor below. The creature was nowhere visible but an eerie silence hung heavy around them save for faint hum of equipment keeping everything running smoothly despite chaos unfolding beneath.

She checked Henry first, relief washing over her upon finding pulse steady albeit weak; then moved onto Maria whose condition remained unchanged—still alive yet unresponsive.

"Come on," Amelia whispered urgently shaking colleague gently by shoulders. "Wake up!"

No reaction except soft moan escaping lips barely parted against pale skin now cold to touch.

Amelia cursed under breath before grabbing comms unit off desk nearby:

"This is Dr Sterling! Anyone there?"

Static crackled through speaker followed eventually by familiar voice—Dr Thomas Lee, their geologist stationed at lower level lab.

"Thomas? Thank god," Amelia sighed into mic. "What's your status down there?"

"We're... we’re okay up here but something happened downstairs." His words came out rushed and panicked.

"What do you mean 'something'?" she demanded sharply while helping Henry sit upright against wall behind him; he groaned softly regaining consciousness slowly.

"I don't know," Thomas replied, fear evident in every syllable. "We heard screams then... things started moving around down there—strange noises like nothing I've ever..."

Amelia cut off his rambling abruptly:

"Alright listen carefully: lock yourselves inside main lab immediately! Do not go outside until further notice!"

She turned towards Henry who was now blinking groggily at her.

"What happened?" he asked weakly rubbing temple where creature struck him earlier.

"You tell me," Amelia retorted handing over comms unit so could hear Thomas' account himself. While they spoke briefly, she grabbed first aid kit from drawer nearby tending wounds on both colleagues—Henry's gash needed stitches but Maria remained unresponsive despite attempts rouse her consciousness again.

"Amelia..." Henry began once finished talking with Thomas.

She looked up meeting his gaze which held mixture fear and disbelief:

"We need to get everyone out of here."

Before she could respond, another scream echoed through comms unit followed by frantic voices pleading for help amidst cacophony sounds too horrifyingly familiar—same wet slithering noises accompanied heavy breathing that sent shivers down their spines.

Amelia grabbed mic back from Henry:

"Thomas! What's going on?"

Silence answered except static bursts punctuating each second ticking away precious time.

Then suddenly, Thomas' voice broke through again but barely recognizable now distorted by terror gripping him tightly:

"It... it got inside—we're trapped!"

Panic surged within Amelia as she realized full extent of situation unfolding around them. They weren't just dealing with some unknown cosmic entity; this thing was intelligent enough to hunt prey systematically, picking off isolated targets one-by-one until none remained.

"We'll come help you," Henry offered weakly trying stand despite obvious pain coursing through his body.

"No!" Amelia snapped sharply pushing him back down onto floor beside Maria. "You're in no condition—we need someone fit if we have any hope saving them."

She grabbed flashlight off desk before rushing towards stairwell leading downward, heart pounding wildly against chest wall like drumbeat urging her onward despite dread coiling tightly around insides.

As she descended into darkness once more—the air grew colder heavier with each step; an oppressive silence hung heavy save for distant echoes of screams still ringing in ears—Amelia couldn't shake feeling something watched unseen from shadows lurking just beyond reach, waiting patiently until right moment strike...

Reaching lower level lab door now slightly ajar letting tendrils cold air seep through crack beneath. She paused listening intently before pushing it open slowly revealing scene straight out of hell itself.

Bodies lay scattered across floor amidst shattered glass and twisted metal; blood mixed with strange viscous substance oozing steadily towards her like tide seeking shore while eerie silence hung heavy save for faint wet slitherings echoing off walls lined by flickering emergency lights casting long macabre shadows dancing grotesquely around carnage.

Amelia stepped inside cautiously scanning area carefully—no sign of Thomas or his team anywhere. Then she heard it: soft whimper coming from behind makeshift barricade erected against far wall using whatever furniture available at hand.

"Thomas?" She called out softly approaching slowly, flashlight beam cutting through darkness revealing figure huddled beneath desk.

It was him alright but barely recognizable—face pale as death with wide eyes staring blankly ahead while trembling uncontrollably despite warmth radiating from nearby heat source presumably meant keep them safe during lockdown. Dr Lisa Chen, their biologist who'd worked closely alongside Maria downstairs.