John pressed himself against the cold metal wall of the kitchen storage unit, heart hammering. The International Cosmic Station had been quiet for three hours. Too quiet.
The distress signal from the mining colony had seemed routine. They’d docked to investigate. Now half the crew was dead and John was hiding in the kitchen.
The door opened.
It entered.
John’s mind tried to reject what he was seeing. The torso was almost human-shaped. But the head—so much hair, moving independently. Each strand writhing like serpents. Dark, reaching, searching. Where a face should be, features that shifted. Eyes in wrong places. A mouth that opened vertically.
It moved through the kitchen slowly. Then it struck.
Both appendages came down on the stainless steel counter. The metal buckled with a deafening CRASH. Again and again. Destroying. Pots crashed. Equipment shattered. It tore the cooking range free—bolts shearing, metal screaming. The shelves came down in cascading destruction.
John stayed frozen. His weapon was in his belt but Doctor Emerson had tried shooting. Had emptied an entire pistol. The creature had kept coming.
The serpent-hair writhed, searching. Several strands extended toward John’s hiding spot. Closer. One strand was three feet away. Two feet. One.
It touched the freezer unit. Paused. Pressed against the metal.
Then withdrew.
The creature moved to the far exit, tore the door off its hinges, and disappeared into the corridor.
John waited. Counted to five hundred. Finally moved. The kitchen was destroyed—every surface broken, every piece of equipment smashed.
He stepped carefully through debris toward the emergency exit. Had to reach the bridge.
Behind him, a single strand of serpent-hair lay among the debris. Detached. Still moving. Still searching.
John didn’t see it follow him.
He reached the bridge twelve minutes later. Emergency sealed the door behind him. Pulled up the station schematic on the main console. The creature was in Section 4 now. Moving through crew quarters. Hunting.
John’s hands shook as he accessed the security feeds. He had to understand what this thing was. Had to find a weakness.
He pulled up the mining colony footage from before they docked.
The screen showed the colony landing bay. Miners unloading cargo from a deep-space expedition. Then one of the containers opened. Something emerged. The Medusa creature. It tore through sixteen people in four minutes.
But then John saw something that stopped his breath.
In the corner of the footage, partially obscured—another shape. Human-sized. Moving differently. It approached one of the dying miners. Reached down.
Changed.
The human shape melted. Reformed. Became one of the miners. Perfect replica. It stood up, walked calmly toward the exit while the Medusa creature continued its rampage.
John’s blood went cold.
There were two of them. Two different species. One that destroyed. One that infiltrated.
He rewound. Watched the shape-shifter again. Studied its movement. The way it walked. The slight hesitation before speaking. The way it didn’t quite match human breathing patterns.
Then John pulled up the station logs. Checked who’d boarded from the mining colony before everything went wrong.
Seven miners evacuated. Seven came aboard.
But only six were logged in the original colony manifest.
One extra.
John pulled up internal security. Started checking crew members. Looking for the tells. The wrong breathing. The hesitation. The too-perfect mimicry.
He found it in Medical Bay footage from two hours ago. Doctor Emerson—supposedly killed by the Medusa creature—had been moving wrong. Too fluid. No fear. He’d walked into the creature’s path deliberately.
Not suicide. Distraction.
While everyone was focused on the monster, the shape-shifter had been moving through the ship. Accessing systems. Opening doors. Herding survivors.
John’s console beeped. Movement alert. Something approaching the bridge.
He pulled up the camera. Commander Sarah Chen stood outside. Face covered in blood and dirt. She raised her hand to the door panel.
John: Sarah? Are you alone?
Sarah (through comms): John, thank God. Let me in. That thing is two sections away. Please.
John watched her carefully. Her breathing was wrong. Too steady for someone who’d been running. Her blood was too uniform—like it had been applied, not sustained through injury.
John: What was Doctor Emerson working on before the distress call?
Sarah: What? John, open the door—
John: His research. What was he studying?
Sarah hesitated. Point-three seconds too long.
Sarah: Xenobiology. Why does it matter? Open the door!
John: His specialty was propulsion systems. Emerson never touched biology.
Sarah went still. Completely still. No breathing. No micro-movements. Like a paused video.
Then she smiled. Wrong. Too wide. Vertical mouth visible for just a frame before snapping back to horizontal.
Not-Sarah: Clever.
The voice was Sarah’s but the cadence was off. Like something had learned the sounds but not the rhythm.
John: What are you?
Not-Sarah: Efficient.
It dropped the pretense. The body shifted. Features melting like wax. Becoming something else. Taller. Thinner. Gray skin. Eyes that glowed faint yellow in the corridor lights.
Not-Sarah: The Medusa hunts. I infiltrate. We work well together. Your species always watches the loud threat. Never sees the quiet one. By the time you realize we’re both here, you’ve already let us in.
John: Why destroy? Why not just… take the station?
Not-Sarah: We don’t want your station. We want your ships. Your navigation data. Your coordinates. The Medusa clears resistance. I access systems. Then we move to the next location. And the next. You’ll evacuate survivors to other stations. We’ll be among them. Your species will spread us across your entire network within months.
John looked at his console. At the creature’s location. At the thing wearing Sarah’s face. At the bigger picture.
John: You made a mistake.
Not-Sarah: Doubtful.
John: You told me your plan. That’s what humans do when they think they’ve already won.
He pulled up the emergency protocol screen. Station-wide lockdown. All sections sealed. Life support reduced to minimal. And one final option—emergency cold shutdown. Drop station temperature to near-freezing. Everything not in thermal suits would enter hypothermia within an hour.
Not-Sarah: You’ll die too.
John: I’m wearing thermal layers. Came prepared when I heard “possible contamination.” And I’ve sealed myself in the one room with independent life support. You’re the one in the corridor.
John activated it. Throughout the station, temperature began dropping. The Medusa creature in Section 4 would slow. The shape-shifter in the corridor would freeze.
Not-Sarah pressed against the door. Started shifting. Trying different forms. Looking for one that could break through.
John: The Medusa hunts. You infiltrate. But neither of you accounted for a human willing to freeze his own station to stop you.
The temperature dropped. Fast. Emergency systems efficient when they needed to be.
Not-Sarah’s movements slowed. The shifting became sluggish. It reformed into Sarah one last time—maybe thinking human form had better cold resistance—and collapsed against the door.
John watched the temperature gauge. Minus fifteen Celsius. Minus twenty. Minus thirty.
The Medusa creature’s movement stopped on his monitor. Frozen in Section 4.
Not-Sarah stopped moving entirely. Flash-frozen in the corridor.
John sat in the bridge for six more hours. Monitoring. Waiting. Making sure they were truly dead.
The cold didn’t kill them—they were alien, maybe they could survive it. But it stopped them. Made them dormant. Gave rescue time to arrive.
When the recovery team finally docked—after John verified every single member through fourteen questions only real crew could answer—they found him shivering in the bridge despite his thermal layers.
But alive.
They found the Medusa creature. Frozen solid in crew quarters.
They found the shape-shifter. Still in Sarah’s form, frozen against the bridge door.
And in the kitchen, in the debris, they found the detached serpent-hair strand. Still alive somehow. Still searching. They incinerated it.
John spent three days in medical. Mild hypothermia. Frostbite on two fingers. Trauma evaluation pending.
Commander Sarah Chen’s real body was found in a storage unit. She’d been dead for hours. Killed quickly when the shape-shifter had needed her form. Small mercy.
Doctor Emerson’s real body was never found. The shape-shifter had taken his form too early. Might have been the first victim.
The investigation revealed two more infiltrators in other stations. Both caught before they could act. John’s warning had spread fast enough.
Twelve months later, John returned to space. Different station. Different assignment. But he always checked the temperature controls first thing.
And he never trusted anyone whose breathing was too perfect.