Seventeen-year-old Lena has never liked winter. But this year the snow seemed different - it shone with a silvery light even on cloudy days. From the window of her room in the Criminal Mill, a small village on the edge of the Frozen Forest, she watched the frost draw an intricate web on the glass. She felt like the forest was calling to her silently, rustling the thin ice twigs. Meanwhile, her friend Iwo, always curious about the world and new challenges, brought a strange object one Saturday. It was a fragment of an old map, found among her grandfather's papers: 'See, there's something written here! 'Only the light of extinguished stars leads to the Gate of the Six Corridors.' What does that even mean?" Lena furrowed her brow. "Maybe it's some kind of clue? I wonder if it's about that big boulder in the heart of the Frozen Forest. My dad once told me that there are ancient tunnels hidden beneath it." Lena and Iwa were soon joined by Tami, a girl with hair as blue as the winter sky, who was famous for her courage. Together they decided to venture deep into the forest. They took torches, warm clothes and a few cheese sandwiches. They took their first steps carefully; there was perfect silence all around and the snow creaked under their boots. Overhead, snowflakes fell lazily, and the dense trees formed something like a corridor. When they reached a large boulder, they felt a slight shiver. Lena pressed the map against the rough surface of the stone. Suddenly, the darkness thickening under the trees seemed to stop time. From afar came a draughty, trembling sound - like the echo of a forgotten melody. "Can you hear it?" whispered Tami. Suddenly, a beam of silvery light emerged from under the boulder, and fresh footprints appeared in the snow - as if someone had just walked this way with their bare feet. Iwo looked at his friends. "Someone or something has overtaken us. What do we do?" Before they had time to think, a murmur came from the depths of the tunnel under the boulder And muffled laughter. The friends looked at each other, each with their hearts beating faster than ever before. Without a word, they moved towards the abyss, where something they never expected to see awaited them.