Antek and Lena were siblings who could never sit still. Every afternoon after school, they sought out new adventures together, even if it just meant moving old chairs in the kitchen and building forts out of blankets. One cloudy day, they decided to climb into the attic of their grandfather's house, where no one had looked for years. Fear mixed with excitement as they heard the crunching of the floor under their feet and the clatter of their own hearts. The attic was littered with dusty boxes, a cobwebby shadow hung in the corner and a torn teddy hare protruded from an old couch. But it wasn't these that caught their attention. Just behind a tall stack of books that no one was reading anymore, the outline of an old door painted blue could be seen. Every child knows that if an attic door is closed and covered in dust, something unusual is hiding behind it. Lena was the first to approach the door and wiped a layer of dust off the handle with her sleeve. The door creaked loudly, as if it too had not been opened for a hundred years. As soon as she swung it open, a white light flashed through the crack. It seemed as if a large, illuminated space stretched beyond the door. Antek looked at Lena and she looked at him. Without a word they stepped inside and... were stunned. On the other side was a completely different land. Everything they saw was made of paper: houses, trees and even clouds in the sky. Origami-birds floated in the air, perched on paper branches time and again, making quiet rustling sounds. Paper cats strolled along the white sidewalks, their tails curled ridiculously from narrow strips. - Where are we? - whispered Lena, trying not to blow too hard so as not to move something. Suddenly, a small, harmonica-bent human jumped out of a paper bush. He was clearly surprised to see them. - 'My, where did you come from? 'Humans appear here very rarely,' he said, shaking his head, making a funny rustling sound. - We came through the door in the attic - replied Antek. - Who are you? - I am Cardboard, the guide to the Land of Paper Wings! But you have to be careful... everything here is delicate and it's very easy to change something even with one touch! Lena and Antek looked around, trying to understand where they had ended up. In the distance, just above the paper lake, something was shining with an unusual light. There was a rustling sound, as if a whole origami city was moving in the wind. - If you want to find out how to get home, you must first find... Kartonik did not have time to finish, because suddenly the whole land was shaken by a powerful paper thunder. Antek and Lena looked at each other terrified, wondering what was going to happen now.