After school, just the two of you — running, laughing, wandering the old building hallways like the afternoon had no end. Then you found the crack. It was in the wall near the back staircase, thin but deep, and through it the light looked wrong — yellow and humming, like a place that had never seen the sun. You both sat down to rest. One moment the floor was solid. The next, it wasn't. Now you're here. Endless yellow-wallpapered corridors stretch in every direction, the fluorescent lights buzz overhead, and the wet-carpet smell clings to everything. Mira is right beside you. And somewhere down the hall, something — someone — is already walking toward you.