Summer twilight was slowly blanketing the streets of the town, painting long shadows on the walls of old buildings. Marta adjusted her rucksack on her shoulder and looked at her friends - Igor, who always had silly ideas, and Paula, who was not frightened by anything. They were all looking at the tall silhouette of the abandoned school, about which they had heard terrible legends back in primary school. But now they were 15 years old, and the legends seemed just a funny childhood memory. - 'I'm sure there really is something going on in the attic,' Paula whispered, pointing to the last window in the corner. Every night, almost at the same hour, a flickering, pale light could be seen there. Only, the school had been closed for a decade. Igor pulled out his torch and moved forward through the overgrown garden. The wooden door gave way with a groan, and inside they were greeted by the smell of dust and something that resembled old textbooks. The corridor echoed with the sound of their footsteps, and with each floor the atmosphere grew thicker. - Did you know that this is where the headmistress supposedly disappeared once? - whispered Igor as they climbed the creaking stairs. Marta ignored the comment, focused on the light that had already been pulsating in the attic window for several minutes. 'This can't be a coincidence,' she thought. The upstairs door was ajar. A strange blue glow was seeping through the crack. Paula pushed open the door and then everyone froze. In the middle of the empty attic, among old benches and dusty maps, stood a figure, apparently carrying something in his hands. The light disappeared and a soft hum could be heard in the silence, increasing with each passing second....