The Secret of the House with Black Curtains

Have you ever seen a person without a shadow? Or a shadow without a person? Just yesterday, Nathaniel, like you, would have answered no. Definitely not! But today... Today, a Shadow is strolling around Madame Swinstlow's house. Alone, without an owner. Nathan and his grandmother discovered it in the living room in the morning. By the way, Nathan's grandmother is the housekeeper at Madame Swinstlow's. And according to her stories, this is not the first peculiarity in this house – the house with black curtains! Nathan and his grandmother decide to get to the bottom of this mysterious matter to help the Shadow find its owner.