As Karolina entered the old antique shop under the Clock, she felt a slight tingle on the back of her neck. Behind her, among the dusty volumes, Michal, her older brother, was looking around. - Did you know that great-grandfather worked here as an apprentice? - he whispered, picking up a leather-bound journal from the shelf. Karolina nodded. They were here for a reason. The shop's owner, the grey-haired Mr Felix, had promised them a substantial reward for finding Master Bernhard's missing watch. What they found, however, exceeded their expectations. Lying between the books was a tiny silver pocket watch with the initials "K.B." engraved on it. Karolina pressed the spring and then time cracked around them like a thin pane of glass. The light flickered, the shop turned into a swirling tunnel, and when Karolina opened her eyes again, she was standing on a cobbled street. Michael was gripping her hand. Carriages were passing all around, the air smelled of coal and rain, and signboards glowed in golden letters: "Warsaw, 1880". The girl clenched the watch in her hand. - Michael... Is this really happening? Suddenly a mysterious figure in a cloak appeared in front of them. She looked at them with black eyes and then threw over her shoulder: - If you want to return to your time, you must find the answer before midnight strikes.... The beating of a clock sounded from afar. Karolina and Michael looked at each other - would they be able to solve the riddle before time ran out?