Maja, Lena, Adam and Igor had packed their backpacks while still in town, planning a weekend in the shadow of Heather Mountain. The view of the wild fields and forests had tempted them for months, and renting out the old rooms in Stasek's guesthouse seemed like the perfect idea before graduation. The guesthouse looked like something straight out of old photographs: the wooden porch creaked under their shoes, the smell of dust and lavender was in the air. The host, grey-bearded Staśko, led them to two adjoining rooms in the attic. - Listen, it's better not to go down to the cellar after dark, the old pipes and it's easy to trip over - he chuckled, before disappearing behind the narrow staircase. The boys were more interested in the vast terrace and the view of the blue range of hills than in the cellar. Lena, sitting by the window, quickly spotted something disturbing - there was an old, broken curtain hanging under one of the ground floor windows, and something like a shadow beneath it. Adam waved his hand. - Probably a spider web, or nothing at all. In the evening, as the last lights in the village went out, they felt strangely isolated. It was so quiet around the guesthouse that every whisper seemed loud. Lena heard a muffled sound, as if someone was treading in the corridor. - Maja, did you hear that? - she asked in a hushed voice. Maja nodded her head. The boys, pretending not to hear anything, pulled back the curtains. But then the door of their room, which had just moments before been carefully closed, began to creak slowly.... Everyone froze. Lena approached the doorknob quietly, but before she could reach her hand, there was a protracted, inexplicable sound from the depths of the corridor - as if someone was moving something heavy across the boards. The light in the corridor flicked on, and Maja saw the shadow of a silhouette on the wall that did not belong to either of them....