The elevator in Building 9 has no 4th floor button. Everyone knows that. But last Tuesday, at 3 AM, I watched the panel light up — 4 — by itself. The doors opened onto a hallway I had never seen, wallpaper from the 1970s, and at the far end, a mirror. In the mirror, the elevator was empty. But I could feel breath on my neck. I slammed the Close button. When the doors opened again, I was on the ground floor. The security guard looked at me and said, "You took the 4th floor too, huh?"