At night, as the light of lanterns spilled through the empty streets of the Old Town, Lena, Kuba and Tom waited at a metro stop that was officially not on any map. Lena, the eldest, cast nervous glances at the entrance marked with a rusty sign: 'Station Zero'. Since her younger brother Simon had disappeared without a trace a week ago, Lena knew she had to try everything. The last message from Simon read: 'Find Station Zero. The key lies underground.' The friends climbed the creaking stairs deep into the underground. Instead of the familiar bustle, the tunnel felt heavy with cool air and the echo of feet bouncing off the damp walls. As they moved along the platform, they noticed an old door with a faded owl symbol on it. Cuba couldn't shake the feeling that someone was watching them. Behind the door, a surprise was waiting: a narrow footbridge led to a huge underground hall, lit up by a greenish glow. In the depths, silhouettes of people in masks loomed, and the walls were covered with maps of unknown worlds. In the middle of the room, next to a huge clock, there was an object resembling a key, which glimmered at the edge of vision. Suddenly the clock struck midnight, and the floor beneath their feet began to move. At the same moment, someone whispered in their ear: 'If you want to find what has been lost, you must move on. But remember: not everything is what it seems.' The friends looked into each other's eyes, feeling that in a moment their lives would change forever....