In a small Italian town on the brink of World War II, ten-year-old Micù has a difficult life—diagnosed with polio, alienated by his peers, and potentially cursed by the local witch, the boy finds an unlikely ally in a mischievous demon named Farfariel, and the two embark on a search for a rare and magical book which might hold the key to turning Micù’s life around.

All that Micù wants from life is to go to school, which his father discourages. Instead, he passes the time with his favorite uncle Tatà, who just returned from years spent living in America with stories galore. But nothing seems to turn out well for Micù. If it weren’t enough that he struggles with polio, the young boy is also afflicted by awful nightmares, endures relentless bullying from his peers, draws constant suspicion from the local villagers, and might even be under a curse!

One day, Micù has a terrifying dream about a mysterious book that promises to solve his problems. Soon after that he meets Farfariel, a mischievous demon invisible to everyone else, and his life is turned upside down. Together with Farfariel, Micù searches for the book, confronting his greatest fears and finding a confidence in himself that he never knew he had.