The old tenement house at 12 Cicha Street always seemed to Lena to be more than just the place where she had lived since childhood. The creaking stairs, cracked walls and stuffy cellars made her wake up in the evenings with the impression that the building breathes with its own dreamy rhythm. There was something peculiar about it - something she could never explain. This year Lena turned seventeen. Her life seemed to be stuck - she would go home after school, listen to music, talk to Damian and Marta, with whom they formed a slightly eccentric but close-knit pack. Everything changed one rainy afternoon when she was in the basement looking for an old childhood album for a project on history. As she pressed the dusty key, the wooden door opened with a groan, revealing the gloomy interior. Withered cobwebs glinted in the faint torchlight, and the smell of damp and dust irritated her nose. She walked past rusted bicycles and forgotten crates until suddenly something completely new caught her eye - a rectangular outline on the wall, like a door she had never seen here before. Intrigued, she touched the surface - it was as cold and smooth as a mirror. A moment later, she heard a quiet, metallic rasp. Before she had time to step back, the wall glowed with a pale blue light. For a second, she had the impression that she could see a completely different space on the other side: towers shrouded in mist, strange plants and, in the distance, the shadow of a human silhouette. Lena froze, feeling her heart pounding like crazy. She reached for her phone and, without taking her eyes off the 'wall', called Damian. As she tried to explain to him what she was seeing, the light suddenly dimmed and something moved on the other side of the portal. The mysterious figure turned its face towards her - and that's when Lena heard her name, spoken quietly but clearly. The voice belonged to someone she had once known, but never expected to hear again. At that moment, the door creaked again - Lena was faced with a choice: to enter the unknown world, or to escape....