Lena stayed after lessons in the old library by the river. The rain tapped on the windows, the clock tinkled with an even tick. Mrs Aniela was sorting books in the back room and sneezing quietly. Lena circulated between the bookcases until she saw a strange section. The caption read: "Atlases of the Worlds", and one volume was missing. A thin, long golden thread dangled from an empty slot. Lena touched the thread, and the bookshelf vibrated like a silent breath. The books rustled, the shelf pulled back and revealed a door. A chill wafted up from below, smelling of rain and baked apples. "Hello?" she whispered, as something rustled like pages being turned. On the table next to her lay an atlas with a dark leather cover. The maps on the cover moved as if breathing slowly. She opened the book to a page with her town and a river. Next to it was a second town, reflected upside down. A compass in the margin whirled until it pointed to the inscription: the Gate. Underneath flashed letters that formed the word 'open'. "Is this just a joke?" she asked, but no one answered. Lena's watch wailed a brief alarm, then went silent. The air thickened and the letters rose like silver birds. The door swung open, revealing a steep cage of darkness and sparks. From inside came a voice that knew her name. "Lena, don't be late," it whispered, carrying an echo like a river. Wet footprints shone on the first step, leading downwards. Lena raised her hand, and the atlas turned another page on its own. A warning flashed in the margin: "Return if in doubt". At the same time, something knocked from the depths of the stairs, three times. Lena took a breath and lifted her foot over the threshold.