The attic of Grandma Marianna's house always smelled of dust, apples and old leather from forgotten suitcases. Lucia and Bartek loved to look up here, especially on rainy weekends when it was impossible to run around the garden. One Saturday afternoon, as the drops rhythmically drummed against the roof, the siblings were searching through a chest full of strange, colourful hats. That's when Lucia noticed something that was always lost in the shadows of the big wardrobes: It was an old wooden clock with a pendulum, a metre high, with a dial cracked like a spider web. The hands stopped exactly at 17:44, just below the word "Mystery", which someone had once carved with a knife on the front of the case. - Look, Bartek! - called out Lucia. - A clock with the word 'Mystery' on it! Do you think it works? Bartek came closer and touched the pendulum. - 'Probably not. But maybe it can be wound? They began to look at the clock carefully. Next to the dial they noticed a small flap. When they opened it, they saw something strange: a small silver keyhole and a button with the word 'Start' written on it. - 'I've never been here...' - whispered Lucia, although they had, after all, been to the attic hundreds of times. Bartek pulled out of his pocket an old key he'd once found in the garden. - Maybe it fits? The key turned slightly and the hands of the clock suddenly began to spin faster and faster. The pendulum moved in a rhythm that no music knew. Glittering specks of light began to flicker around the siblings, as if Christmas lights had been strung in the air. Suddenly they felt a jerk, as if the world had spun around them. The floor disappeared from under their feet and the silence was broken by the deafening sound of a bell. They opened their eyes and. they were no longer in their grandmother's attic. In front of them stretched a wide, cobbled street. People were walking around in costumes as if they were from old films, and a pair of horse-drawn carriages drove across the square. Lucia squeezed Bartek's hand. - Are we... Did we just really... But before she could finish, they heard a strange voice behind them: - You guys aren't from here, are you? They turned around slowly...