My phone alarm was acting up, going off at random hours. One night, it woke me at 3:33 a.m. with the message: “Come outside.” Thinking it was some glitch, I ignored it. The next morning, there was a note slipped under my door: “You missed us. Try again tonight.”

Curious, I decided to play along. At 3:33 a.m., when the alarm buzzed again. Terrified but curious, I stepped outside. My phone lit up with one final message: “Turn around.” When I did, there was nothing there. “Who’s there?” I called out. A voice, distant but clear, replied, “You answered. That’s all we needed.” Since that night, my phone’s been silent. I still don’t know who they were—or what would’ve happened if I hadn’t answered.