"I Opened a Stranger’s Letter by Mistake—Now I'm Being Watched"

It was just a letter. A plain white envelope, no return address, my apartment number scribbled in blue ink. I didn’t think twice when I picked it up from the mail slot. Bills, junk mail, and a single envelope addressed to “A. Miller.” That was me—or so I thought.

I slit it open absentmindedly as I walked up to my third-floor apartment. Inside was a single sheet of paper, neatly typed, with no signature:

> "We know what you did. You’ve been warned once. There won’t be another."



I stopped in my tracks.

I read it again. And again. My heart began to pound—not because I understood what it meant, but because I didn’t. Was this some kind of prank? A mistake?

It wasn’t until I glanced at the envelope again that I noticed the handwriting more carefully. “A. Miller,” yes—but the number wasn’t 3C. It was 3E.

I lived in 3C.

I stared down the hallway. 3E was just across from me. I didn’t know the person who lived there. I had only moved into this building six weeks ago, and I'd never seen anyone come or go from that door. The name on the buzzer said “A. Miller,” just like mine—but what were the odds?

I slid the letter back into the envelope and crossed the hall. I raised my hand to knock—then stopped.

What if they thought I’d opened it on purpose?

I looked again at the door. No sound, no light beneath it. Just silence. I returned to my apartment, locked the door, and placed the letter on the table.

That night, I barely slept. Every creak of the floorboards above, every gust of wind rattling the fire escape made me jump. I kept thinking about the letter’s words: There won’t be another.

By morning, I decided to forget it. A simple mistake. Maybe it was some weird joke between friends or roommates. I’d return the letter when I had the chance and be done with it.

But when I checked the hallway the next day, something had changed.

The name on the buzzer for 3E was gone.

Just blank metal where it used to say “A. Miller.”


---

That evening, I came home to find the envelope was missing from my kitchen table.

I froze.

I live alone. No one else has a key.

The lock wasn’t broken. Nothing else was touched. Just the letter—gone.

I searched the apartment from top to bottom. Every drawer, closet, cabinet. I even checked under the sink, behind the fridge. Nothing. Just an empty space where the letter had been.

Then, as I passed my window, I noticed something odd.

Across the street, in the apartment directly opposite mine, a light flickered on.

The room was dark except for a single bulb. A figure stood there, motionless. Watching.

I stepped back from the glass instinctively.

When I peeked again, they were gone.


---

The next morning, I called the landlord and asked about the tenant in 3E. He sounded puzzled.

“No one’s lived in that unit for almost a year,” he said. “Last guy skipped out on rent. You sure you saw a name on the buzzer?”

“I’m certain,” I replied.

He paused. “You okay, Ms. Miller?”

“Yeah,” I lied.

But I wasn’t.

I started noticing things. My apartment felt... wrong. Things were moved slightly. My keys on the counter were flipped upside down. My bathroom mirror had a faint smudge—like someone had breathed on it.

And every night, the light across the street flicked on. Just for a moment. Always at the same time: 2:03 AM.


---

One night, I stayed up, staring out the window, determined to catch them. When the light came on, I was ready. I used my phone to snap a photo quickly, hands shaking.

Then I zoomed in.

The window across the street was boarded up from the inside.

There was no way someone could stand there.

No way the light could turn on.

I dropped my phone.

I was being watched.

But by what?

Or who?


---

I finally went to the police. They were polite, took down my statement, nodded a lot, told me it was probably a misunderstanding or anxiety. One officer offered to send a patrol car by. That night, I felt a bit safer.

Until I returned home and found a second letter slipped under my door.

This time, the envelope had no name. No apartment number.

Just one line inside:

> "You should have stayed out of it."



I moved out the next morning.

Didn’t pack much. Left most of my furniture behind. I didn’t care. I just wanted to be gone.

Now I live two states away. I changed my number. Got a new job. I check all my mail carefully.

But last week, I got a call from an unknown number. The voicemail was empty—just faint breathing.

And this morning, I found a white envelope on my doorstep.

No return address. No markings.

I haven’t opened it.

Yet.