The abandoned high school building on Vulture Street hid more than old benches and cracked blackboards. The whole neighbourhood said that things happened there after dark that were better not seen, and that the shadows in the corridors were denser than anywhere else in the city. Seventeen-year-old Lena knew all these stories, but that evening, intrigued by the disappearance of her friend Mai, she stood at the school's closed door with a torch in her hand and her heart beating like crazy. Her footsteps echoed off the walls as she climbed to the fourth floor, to the former biology room. There, rumour had it, someone had created a portal to another world, and Maja had recently written to her about strange dreams in which she walked through a mirror to see a world without colours. Lena couldn't turn back now. Suddenly she heard a soft rustling from behind the closed door of the laboratory. A push - the creak of wood - the forgotten interior appeared in the torchlight. Against the wall, right next to the former teacher's table, she noticed a circle scrawled in chalk. In the centre, bizarre runes shone. Lena swallowed her saliva and slowly approached. She noticed Mai's notebook on the floor, open to a page written in her small handwriting: "...if you read this out loud, the door will open. I don't know if I can come back. If you want to find me, you have to go in. But remember: you can only go to the other side once." Lena felt an icy shudder. She picked up the notebook, looked at the runes and breathed deeply. Everything in her screamed to turn and run away, but instead she raised her voice and began to read the spell. The air grew thick around her, the torchlight spilled strangely on the walls, and her reflection in the broken mirror shimmered like water.... And suddenly - she heard a quiet whisper from the other side: "Lena, don't go through..."