Lena really enjoyed her autumn walks in the park. One afternoon, when a lot of leaves had already fallen and everywhere was colourful, Lena noticed something different than usual under a large chestnut tree. Where only a bench had always stood, a wooden door had appeared, tall and overgrown with vines. Lena took a closer look at the doors. From a distance they looked ordinary, but when she pressed the handle, she felt a gentle gust of wind and heard quiet giggles. Was it the leaves giggling? Lena looked through the ajar door and rubbed her eyes in surprise! On the other side was a colourful world where leaves were not lying on the ground, but flying like birds. Squirrels ran along the golden branches, and one of them, wearing a blue hat, waved a paw at Lena. - Hello, Lena! - called out the squirrel. - It's good that you came. We need your help! At the same moment an acorn flew past Lena, who muttered: - Watch out for flying acorns! Lena felt her heart beating faster. She was just standing on the threshold of a new adventure. The door creaked slightly, as if inviting her to enter....