The old Stanisław Lem High School stood in the heart of the Golden City like a relic of a bygone era. The brick walls, covered here and there with ivy, seemed to be silent witnesses to a thousand stories. However, the most striking feature was the soaring Clock Tower, the sound of which resounded daily, reminding pupils of the next lesson and teachers of the end of recess. Ola, Igor and Weronika met under the tower almost every day after lessons. Usually they talked about future plans, exams or the latest films, but this afternoon was different. It was June, the air smelled of a storm and the school was almost completely deserted. - Did you see that? - Veronica asked suddenly, pointing to a small door at the back of the tower. Steel, with a crumbled lock, it looked as if it shouldn't have been opened for years. Igor approached first. - I swear I've never seen them here. Maybe they were always padlocked? Ola crouched down and shone the torch from her phone. On the ground, around the threshold, footprints were visible - fresh, as if someone had entered just a few hours before. In addition, there was an old brass handle lying by the door, which did not match any other door in the school. - 'Come on, let's check,' whispered Igor, feeling an unfamiliar excitement. They walked through the door, which opened surprisingly easily, with a quiet groaning of the hinges. Behind them, a narrow staircase led down into the depths of the tower. The walls were covered with paintings, the partially obliterated dates and names evoking echoes of yesteryear. It was stuffy and dark, and the air smelled of dust and old age. - 'Something's not right here,' Ola said quietly. - 'After all, there shouldn't be any descent under the tower, it's not on the school plans. As they descended lower and lower, they felt the tension build up. Each step echoed off the walls, and the sound of their breathing mingled with the clatter of their hearts. Suddenly Igor stopped abruptly. - 'Did you hear that? - he whispered, pointing to a closed door at the end of the corridor. There was a rustling sound on the other side, as if someone was moving something heavy across the floor, then there was silence for a moment.... Then the light of the torch fell on something lying against the wall: an old, yellowed photograph showing three teenagers standing exactly where Ola, Igor and Veronika now were. All three were wearing school uniforms from decades ago. On the back of the photo, in red crayon, someone had written the date: 14 June 1972. Behind the door something moved again. The three friends exchanged quick glances, and Igor, despite the tightness in his throat, put his hand on the handle....