I finally moved into my own place after graduation. A third-floor walk-up in a building so old the floorboards groaned if you even thought about walking on them. The previous tenant, a photography student named Elias, had left a stack of developed Polaroids in a shoebox under the radiator.

They were all photos of the apartment. Every single one. But they were dated by time, not day.

1:00 PM, 2:30 PM, 3:45 PM.

Curious, I began to look through them. They were mundane until I hit the one labeled 4:12 PM. In that photo, my living room looked different. There was a thin, black cord snaking out from under the baseboard that wasn't there in real life. I checked the next one, 4:13 PM. The cord was longer, reaching the leg of the coffee table.

I laughed it off. A long-exposure prank or some student art project. I put the box in the closet and went about my day.

At 4:00 PM, I sat down with a cup of coffee. I remembered the box. I looked at the baseboard near the radiator. Nothing. Just the dust of a century. I looked at my watch. 4:11 PM.

I felt a sudden, sharp prick on my ankle. Like a needle. I looked down, but my jeans were intact.

I grabbed my phone and opened the camera app. I don’t know why, but I felt the need to see the room through a lens. I pointed it at the radiator. On the screen, a thick, black vein not a cord, something organic and pulsing was slithering out from the wall. I looked at the floor with my bare eyes. Empty.

I looked back at the screen. The vein had reached my foot.

I jumped back, spilling my coffee. On the phone screen, the black thing retreated instantly. I realized then that it reacted to the "observation." It only moved when it wasn't being watched through the filter of the camera.

I stood in the middle of the room, holding my phone out like a shield. I did a slow 360-degree turn. On the screen, the apartment was infested. Black, glistening tendrils hung from the ceiling like weeping willow branches. A pair of pale, elongated hands were gripped around the edges of my bathroom door, as if something were trying to pull the entire room into the hallway.

I looked at the bathroom door with my own eyes. It was shut. Normal. Safe.

Then, my phone vibrated. A notification from an unknown number.

"The battery is at 4%."

I panicked. I ran for my charger in the bedroom. I kept the phone pointed in front of me. On the screen, the bed wasn't a bed. It was a mound of grey, translucent fabric that seemed to be breathing.

I reached for the outlet. On the screen, a mouth was opening in the wall where the plug should be a wide, lipless gape filled with rows of needle-teeth.

"Don't turn on the faucets," a voice whispered from the phone’s speaker. It was my own voice. "It uses the pipes to hear."

The screen flickered. 3%.

I backed away into the living room, my heart hammering. I needed to leave. I reached for the front door handle. On the screen, the handle was a human eye, dilated and bloodshot, staring directly into the lens.

"Rule number five," the phone whispered. "The things forage all day. You don't want them in your flat. I promise."

I dropped the phone. The screen cracked, but it stayed on. From my position on the floor, I could see the reflection in the cracked glass. The "me" in the phone wasn't standing in the living room. He was lying in a hospital bed. Sarah was there, crying. A doctor was leaning over, holding a needle.

"He's reacting," the doctor said. "Increase the dosage."

I felt another sting in my arm.

I looked at the front door with my bare eyes. It was just wood. I grabbed the handle and yanked. It wouldn't budge. I looked at the floor. The shoebox was back under the radiator. It was open.

I crawled toward it. I pulled out the last photo in the stack. It wasn't a Polaroid. It was a digital print of the room I was standing in right now. In the photo, I was on my knees, looking at a photo. And behind me, the "Still Man" was leaning down, his face a bullet on a shell casing, his red lips inches from my ear.

"You're awake again," he whispered.

I didn't turn around. I couldn't. My eyes were locked on the phone screen as the battery hit 1%.

In the final second of light, I saw the reflection of the room change. The black tendrils vanished. The teeth in the wall disappeared. For one beautiful, terrifying moment, I saw the hospital room clearly. I saw the train tracks. I saw the black-and-yellow bars.

Then the screen went black.

I’m sitting in the dark now. I can hear the floorboards groaning, but I’m not moving. Something is whistling near the front door.

Da da dada da dum.

I’m reaching for the shoebox. I need to find the rule about what happens when the lights go o

ut. But I think I already know.