It was 12:07 a.m. when I heard a knock at my door. I live alone, and no one ever visits at this hour. Heart pounding, I peeked through the peephole—and there was a man I’d never seen before.

He smiled politely and said, “I think you dropped this.” In his hand was a small, plain envelope. Confused, I took it—then he vanished before I could even say a word.

Curiosity won. I opened the envelope. Inside were dozens of photos… of me. My apartment. My daily routines. And on the last photo was a note: “I know what you did.”

I panicked. Who could know? I hadn’t told anyone about… well, the thing I thought I’d buried forever. The next morning, I realized my front door had been unlocked. Nothing was stolen, but everything felt different. Someone had been inside. Someone had been watching.

Weeks later, I got another envelope. This time, it contained a single key—and a new note: “You can run, but you can’t hide.”

I moved immediately. But even now, every knock at the door makes my blood run cold.