Twelve-year-old Mariana is an avid reader. But it never occurred to her that she herself would end up in a story full of magic and wonder. Together with her family, the girl finds herself on an island that is not on the map. And it turns out that the house in which they settled, lives its life: it always changes the color of the wallpaper and hides the things of the inhabitants. What\'s more, at night, a mysterious girl appears out of nowhere in Maryanka\'s room and asks for help. So Mariana decides to reveal all the secrets of the Hidden Island. And on the way she will face both magical trials and real teenage problems: finding friends at school, misunderstandings with parents, love, the first steps towards the realization of dreams and gradual maturation.