The Stained Index Card

The book was on Oceanic Trade Routes, 1880-1920. I’d grabbed it off the shelf because the spine was a nice shade of blue and I needed to look like I was doing my history homework. My actual homework was still a blank page in my bag. I wasn't really reading. I was just letting the silence of the place soak in, trying to forget the argument with my mum that morning. The book felt heavy and important in my hands, a solid block of forgotten knowledge.

My thumb traced the edge of the paper. I felt it before I saw it. A slight thickness. A subtle lump just inside the back cover, where the heavy card had been glued to the binding. It wasn't just a wrinkle. It was a deliberate slice, so fine I almost missed it, sealed with a careful line of what looked like rubber cement. Curiosity is a stupid, twitchy thing. Before I could think it through, my thumbnail was digging at the seam.

It came away with a faint tearing sound, shockingly loud in the quiet. Inside the hollowed-out space, no bigger than a postage stamp, sat a tiny black square of plastic. A micro-SD card. It wasn’t tucked in; it was held by a sliver of clear tape. My heart gave a painful little thump against my ribs. This wasn’t a lost item. This was a hidden one. My first thought was that I should close the book, put it back on the shelf, and walk away. Forget I ever saw it. Pick up a book on the Tudors instead. My second thought was to slide the little black square out and slip it into my pocket.

I looked around. The librarian, Mrs. Gable, was staring at her computer screen, her face washed out by its glow. An old man in the corner was asleep, his newspaper tented over his face. No one was watching. My fingers felt clumsy and huge as I worked the card free. It was weightless. Five millimetres of trouble that felt like it was burning a hole in my palm. I pressed the flap of paper back down, closed the book, and jammed it back onto the shelf in the wrong section. My hands were sweating. I walked out of the library without looking back, the tiny square digging into the seam of my jeans pocket.

The wind was cold, carrying the smell of wet leaves and car exhaust. It funnelled down the street, pushing me along. Every person who glanced my way felt like a threat. The man waiting for the bus, the woman walking her dog, the courier leaning against his van. Were they looking at me? Did they know? God, that was stupid. How could they know? I pulled the collar of my jacket up, my knuckles white as I gripped the strap of my bag. The card was still in my pocket. I could feel its sharp little corners through the denim.

I didn't go home. I went to Carmen’s.

Her house was a fifteen-minute walk away, a semi-detached place with a peeling front door and a garden full of half-finished projects. Carmen’s dad was always starting something. I knocked, the sound echoing in the sudden quiet of the suburban street. She opened it on the second knock, her brow furrowed in concentration. She was wearing a paint-stained hoodie and holding a soldering iron.

“What?” she said. It wasn’t unfriendly. It was just Carmen.

“Need your help,” I said, my voice sounding thin.

She looked me up and down, then glanced past me at the empty street. Her eyes, which usually missed nothing, seemed to linger on the shadows for a second too long. She sighed, a puff of weary air. “Get in. And wipe your feet.”

Her room was organized chaos. Circuit boards and wires covered half her desk, while the other half was a fortress of textbooks. A laptop was open, lines of code scrolling slowly down the screen. The air smelled of solder, ozone, and the faint, sweet scent of the raspberry tea she always drank.

I took the card out of my pocket and placed it on her desk, next to a detached robot arm she was building. It looked impossibly small and insignificant in the clutter.

“Found this,” I said.

She picked it up with a pair of tweezers, holding it under her desk lamp. She turned it over and over. “Where?”

“Library book.”

“Right.” She didn’t ask any more questions. She didn’t need to. She just pulled a small USB adapter from a drawer, slotted the card in with a precise click, and plugged it into her laptop. Her fingers moved across the keyboard, tapping out commands. I just stood there, shifting my weight from foot to foot, my hands shoved deep in my pockets. I kept thinking about the slice in the book cover. So neat. So professional.

“Password protected,” she said, not looking at me. “And the partition is hidden. Whoever did this wasn't an amateur.”

“Can you get in?”

“Maybe.” She chewed on her lower lip. “Gonna take a while to run a bypass. Go sit down. You’re making the floorboards creak.”

I sat on the edge of her bed, watching the lines of code crawl across her screen. The minutes stretched out. The only sounds were her quiet typing and the hum of the computer’s fan. Outside, the sky was turning a bruised purple. A car passed, its headlights sweeping across the ceiling, and I flinched. Carmen didn't seem to notice.

“Anything?” I asked after what felt like an hour.

“Patience,” she muttered. A progress bar was inching its way across a black dialogue box. 12%. 13%. It was excruciating. I got up and walked to the window, peering through a gap in the blinds.

The street was quiet. Orange streetlights cast long, distorted shadows. A black car was parked across the road, a few houses down. I hadn't noticed it when I came in. It was a generic saloon, the kind you see everywhere and never remember. But it felt wrong. It was too clean. Too still. No one was inside, at least not that I could see.

“Bronson,” Carmen’s voice was sharp. I turned.

“What?”

“Look at this.”

I walked back over to the desk. The progress bar was gone. In its place was a file directory. It was mostly empty. Just one folder, labelled with a random string of numbers and letters. Inside it, a single file. It didn't have a normal extension. It was just called ‘INDEX’.

The Ghost in the Code

“It’s corrupted,” she said, pointing at the file properties. “Or parts of it are, anyway. It’s like a puzzle where half the pieces are missing. I can try to reconstruct it, but it’ll be patchy.”

“Do it.”

She started another program. This one looked different. It was a visualiser, showing blocks of data as a shifting, three-dimensional shape. Green blocks were stable, red ones were corrupted. Most of it was red. She worked for another half hour, isolating fragments, trying to stitch them together. I went back to the window. The black car was still there.

A flicker of movement. The streetlight glinted off something. A pair of binoculars. Someone was in the driver’s seat, sunk low. They were watching the house. Watching this window. My blood went cold. I stumbled back from the blinds, my heart hammering against my ribs like a trapped bird.

“Carmen.”

My voice was a croak. She didn’t look up.

“Almost got something,” she mumbled, completely absorbed. “Just a string of text… weird syntax.”

“Someone’s out there,” I whispered. “Watching us.”

That got her attention. She swivelled in her chair, her face pale in the monitor's glow. “What do you mean?”

“A car. Across the street. There’s a man inside. He was looking up here.”

She stood up slowly and came over to the window, moving cautiously. She peeked through the same gap I had. Her breath hitched. She didn't say anything, just stared for a long moment before backing away, her movements stiff.

“Okay,” she said, her voice unnaturally calm. “Okay.”

We both looked at the laptop, at the meaningless, shifting blocks of data. The little black card on her desk suddenly seemed like a bomb.

“What is this stuff?” I asked.

“I don’t know.” She went back to her chair, her focus now sharp and frantic. Her fingers flew across the keyboard. “The fragments I pulled… it’s not a message. It’s more like a ledger. Dates. Place names. And single words. Like code names, maybe.”

“For what?”

“How should I know?” she snapped, the fear finally showing. “This is… this is not good, Bronson.”

The program she was running beeped. A small piece of data had been successfully reconstructed. A single, clear fragment from the corrupted file. It wasn't a name or a date. It was a single word.

Nightingale.

It flickered on the screen. Utterly meaningless. Just a word. But looking at it sent a fresh wave of ice through my veins. It felt ancient and dangerous, a key to a door we should never have tried to open.

The single word flickered on the screen, meaningless and yet utterly terrifying. And from the street below, a car door slammed shut with unnerving finality.