When the clock on the city tower struck midnight, Sara, Damian and Lena were already standing at the iron gate of the old mental hospital. The silent, moss-covered walls reflected the moonlight, and as the wind rustled the leaves around their feet, each of them could feel the tension in the air. Legends were whispered about such a place - they said there was a portal in the underground through which people disappeared. They had long dreamed of discovering something amazing, but on this night curiosity fought fear. The rusted door gave way with a groan, breaking the silence in the corridors. Inside, the smell was cold and musty, and the lights on their phones barely illuminated the scratched walls. Damian led the way - the fastest to breathe, but he pretended to be brave. On the second floor they found a lift with a slammed door. Lena noticed that a spiral symbol was engraved on it. "It's a sign of passage," she said quietly. They descended to the basement, where the lights were no longer sufficient and a strange fog could be felt around the corner. Sara stumbled over something - it turned out to be an old, crooked sign that read: "This is where people's world ends". Behind it, they discovered a small gap - a grey, pulsing light shone through it. They tilted their heads, and Lena hissed quietly: "There's something there... it's moving!" Then the walls began to tremble gently, and a sound like the whispering of a thousand voices came from the portal. Damian felt the ground tremble beneath his feet. Should they run away or, on the contrary, go further in? At that moment, the light from the portal exploded and a wave of cold so thick that they could hardly breathe ran down the corridor. All three froze in place, staring at something indescribable that had just begun to emerge from behind the mist....