Zoe's eyes snapped open in the darkness.

  Wrong. Everything was wrong. The walls, the smell, the taste of metal in her mouth. Her heart hammered against her ribs, a frantic beat pumping raw adrenaline through her veins.

  Trapped. Confined. They left you.

  The thoughts felt alien, but terrifyingly real. Urgent. Terrifying. Someone had put her here, in this white room with its antiseptic stench and humming machines. Someone had abandoned her while she was helpless.

  Get out. Run. Now.

  She didn't think. Couldn't think. Her body moved on pure instinct, assassin reflexes taking over as she rolled off the medical bed. Her legs nearly buckled, but she stumbled forward, driven by a raw, unthinking panic.

  The door. She had to reach the door.

  Behind her, monitors began to alarm as sensors lost contact with her body. But she was already moving, already gone, her bare feet silent against the cold deck plates.

  In the corridor, something impossible happened.

  Her skin began to fade.

  As the need to disappear became everything, her body responded. [Ghost Protocol] activated without her scout suit, far beyond her normal abilities. Her skin became translucent, then invisible, the infection unlocking capabilities she'd never possessed.

  The hospital scrubs fell away, feeling too solid, too visible. She left them crumpled on the infirmary floor as she drifted unseen through the darkened corridor, her vision blurring at the edges.

  Hide. Disappear. They can't find you if they can't see you.

  The ship's passages became a maze of shadows and silence. Her [Silent Step] abilities, enhanced beyond recognition, allowed her to phase short distances through solid matter. She was a ghost haunting her own home, driven by fears she couldn't name and reflexes she couldn't control.

  But Zoe was already gone.

  "Goddammit, Zoe," Luca muttered, pushing the cart through the infirmary doors. "Where the hell are you?"

  Shaking his head, he forced himself to focus. Five people still needed treatment. He shoved the panic down. No time.

  First, he checked the others for signs of the green tendrils. Emily on her bed, pale but stable. Ryan unconscious behind his oxygen mask. Joey collapsed where he'd fallen, fever burning in his cheeks. Nothing. No spreading infection visible on any of them yet.

  Thank god. Zoe was the first.

  He wheeled the cart to Danny's medical pod and extended the injection port. The cartridge slotted in perfectly. It was TL9 technology, but still compatible with their medical systems. A small miracle in the middle of this nightmare.

  He pressed the activation sequence.

  Red mist spread through the blue gel surrounding Danny's unconscious form, the anti-invasive cytobiotic dispersing evenly throughout the pod's life support matrix. Danny's monitors showed no immediate change, but the treatment was active.

  Next, Chris's pod. Luca sealed the glass canopy and injected the second cartridge. Another cloud of red mist, another life hanging in the balance.

  Thirty minutes. Thirty fucking minutes before I can move Chris out and get someone else in.

  He checked the central monitor displaying everyone's vitals. Five steady readouts showing heartbeats and brain activity. The sixth, Zoe's, displayed only null values. No signal. No contact.

  Her hospital scrubs lay crumpled on the floor where she'd left them.

  "Pixel," Luca called softly. The kitten appeared from beneath Emily's bed, her markings pulsing anxious purple. "We need to find her."

  He stepped into the corridor. The ship felt wrong: too quiet, too empty. Like something dangerous was moving through its passages.

  Think like Zoe. Where would she go?

  He started with the habitation deck, activating [Heightened Awareness]. His senses expanded, picking up the faint vibrations of the ship's systems, the soft hiss of air through ventilation, the almost-silent hum of lights in standby mode. But underneath it all, nothing. No heartbeat. No breathing. No warmth signature that shouldn't be there.

  Zoe's cabin first. The door slid open to reveal her personal space, neat, organized, with a few photos on the small desk. Luca stepped inside, scanning methodically. He checked under the bed, behind the wardrobe, in the tiny closet space.

  "Zoe!" he called softly. "It's me. I have the cure. You don't have to hide."

  Everything looked normal until he pressed his palm against the desk surface.

  Still warm. This was body heat, not the ship's residual energy. Someone had been sitting here minutes ago, maybe less.

  She was just here. Just here.

  Pixel padded into the room and froze. Her fur stood on end as she stared at the empty space beside the desk chair, hissing at nothing Luca could see. But her eyes tracked something, following a movement that wasn't there.

  She's here? Right now?

  The realization hit him like ice water. Zoe wasn't hiding somewhere else in the ship. She was here, in this room, invisible and silent, close enough to reach out and touch him.

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  "Zoe," he whispered, his voice barely audible. "I know you're here."

  Pixel's hissing stopped. But instead of relaxing, the kitten approached the same empty space she'd been hissing at, sniffing cautiously. Then she began pawing at nothing, her claws swiping through empty air. Her back arched, fur standing on end again, but now she looked confused rather than threatened.

  What the hell?

  Pixel circled the spot, sniffing, pawing, searching for something that had been there moments ago but was now... gone like it had simply ceased to exist in that location.

  How did she—? There was no sound. No movement. How do you just... disappear?

  Luca felt a chill run down his spine. Whatever the infection had done to Zoe's abilities, it was beyond anything he understood. She hadn't walked away or crept to another hiding spot. She'd been there and then she simply wasn't.

  Danny's cabin next. The door opened to his tidy and organized room. Notebooks were scattered across the desk, sample containers arranged in careful rows, star charts pinned to the walls. Luca checked every corner, every shadow, running his hands along surfaces to check for warmth. Under the desk, behind the chair, in the equipment lockers.

  "Zoe, I know you're scared!" he called louder. "But we figured it out. The infection, we can stop it!"

  The lounge was unnervingly still. This space where they'd spent so many evenings, playing cards, sharing stories, building the bonds that made them more than just a crew. Now it sat empty, chairs pushed under tables, the main display screen dark and reflective.

  "Zoe!" His voice echoed in the empty space. "Please! You're going to die if I can't treat you!"

  Luca activated [Pattern Recognition], scanning for anything out of place. The ability highlighted subtle disturbances, a chair slightly askew, a cushion compressed as if someone had recently sat there, scratch marks on the deck plating that looked fresh.

  His focus narrowed to that of a hunter. He checked under every table, behind every chair, in every shadow where a person could hide. His fingers traced the warm spots where someone had touched surfaces, following a trail that led toward the galley.

  In the galley, one of the upper storage compartments was slightly ajar. Large enough for a person Zoe's size to fit inside, if they were desperate enough. But when he opened it fully, he found only supplies.

  She's always one step ahead. Moving when I'm not looking.

  The command deck felt different. Professional, sterile, but somehow more threatening in the darkness. The bridge was a maze of shadows cast by instrument panels and command chairs. Luca moved carefully, checking behind each station.

  He moved instinctively to Zoe's navigation station. Her chair was still warm, definitely warm, not just residual heat from the ship's systems.

  He was about to leave when something on her display caught his eye. The navigation plot was still active, showing their course toward the asteroid belt. But something was wrong with the trajectory.

  Luca leaned closer, checking the coordinates. They were seventeen degrees off their original heading. A significant course correction that would take them... where? The new trajectory led toward empty space, away from their surveying mission, away from any charted destinations.

  This wasn't random. This was deliberate.

  The course change was too precise, too calculated to be the work of someone confused or panicked. Someone had sat at this station, accessed the navigation controls, and inputted specific coordinates with a clear destination in mind.

  She's not just hiding. She's directing us somewhere.

  "Zoe!" he called into the empty bridge, his voice carrying across the command stations. "I know you can hear me! Whatever this thing is doing to you, we can fix it!"

  He could correct the course easily, restore their original path with a few keystrokes. But something stopped him. If the infection was driving her to make navigation changes, there might be a reason. A purpose he didn't understand yet.

  And if she could change their course once, she could do it again.

  He left the course unchanged and stepped away from the console, a new understanding forming in his mind. This was no longer the desperate flight of a sick person. This was strategy.

  He activated [Proximity Threat Map], pushing the ability to its limits. For ten seconds, his enhanced interface tried to map all nearby positions, movement paths, and acoustic signatures. The overlay showed nothing. Zoe was a complete void in his sensory awareness.

  The labs were dark, filled with equipment that cast strange shadows in the emergency lighting. Luca moved between workstations, checking under benches, behind storage units, in equipment lockers large enough to hold a person.

  But as he searched, his enhanced hearing caught something that made him stop. The trace of movement above him... above the ceiling.

  He looked up at the ventilation grating. It was secure, locked in place, but something was wrong. The screws looked different. Cleaner, suggesting they had been recently removed and carefully replaced.

  She's not just moving through corridors. She's using the entire ship.

  Luca activated [Pattern Recognition], and the ability highlighted more details he'd missed. Scuff marks on the ductwork. A faint smudge on the grating that could have been from bare skin. Disturbed dust patterns that suggested recent passage.

  Three-dimensional movement. She's not bound by doors or corridors anymore.

  A cold dread trickled down Luca's spine. Zoe wasn't just hiding in the ship's normal spaces. She was moving through its bones, its hidden passages, the network of ventilation and maintenance shafts that ran behind every wall and above every ceiling.

  She could be anywhere. Listening from above. Watching from below. Moving through spaces he couldn't access, couldn't search, couldn't predict.

  How do you hunt someone who can move through walls?

  Engineering deck. Power systems, environmental controls, the generator room where he'd connected the cable hours ago. Here, the mechanical noise was louder: pumps, fans, electrical hum, providing perfect acoustic cover for someone who didn't want to be found.

  "I'm not giving up on you!" he yelled over the machinery noise. "Do you hear me, Zoe? I'm not leaving you!"

  Luca checked behind every piece of machinery, under every access panel, in every maintenance alcove. The spaces felt abandoned, but his enhanced senses were picking up traces. A handprint on a power coupling that was still warm. Scuff marks on deck plating that looked fresh. The faintest chemical signature that might have been skin oils or sweat.

  She's been everywhere I've searched. Following me or staying ahead of me.

  Finally, the hangar deck. Back where this nightmare had started, past the still-humming SynthCrafter and SpectraForge units. The space felt more ominous now, filled with equipment that created a hundred potential hiding spots.

  That's when he saw it.

  The armory door stood open.

  Luca's blood went cold. He approached slowly and checked the weapon inventory. Most of the equipment was still secure in its cases, but one item was missing.

  Zoe's energy dagger.

  She's not just hiding anymore. She's hunting.

  The weapon could cut through hull plating. In the hands of an enhanced, invisible infiltrator, it was a guaranteed kill against anyone who couldn't see her coming.

  But preparing for what? What is she getting ready to fight?

  Luca looked around the hangar with new eyes. The warm desk in her cabin. The deliberate course correction. The ventilation access routes. The missing weapon.

  Each discovery painted a picture he didn't want to see. Zoe moved with purpose. Gathering intelligence, securing mobility routes, changing their destination, arming herself. She was preparing for a mission.

  But what's the mission? And who's the target?

  "Zoe," he called softly. "I know you're scared. But we have the cure. I can help you."

  Only silence answered.

  And somewhere in that silence, he knew she was listening. Armed. Enhanced. Invisible.

  Pixel hissed again, backing away from a shadow that looked exactly like every other shadow in the dim hangar.

  But Luca was starting to understand that Pixel could see things he couldn't.

  Things that might not want to be found.

  Then the artificial gravity cut off.

  Luca's feet left the deck. Pixel yowled as she floated upward, her paws scrambling for purchase on nothing. Equipment that had been secured to tables began to drift, and in the sudden weightlessness, every shadow became three-dimensional, a place where someone could hide above, below, or at any angle.

  In the sudden, disorienting silence of zero-g, he realized he couldn't even hear her coming.

  How the hell do you fight a ghost?