Giovanni is a young boy living on the outskirts of a small, rustic village. His mother is confined to bed, and his father has not come home since departing for work on a fishing boat. An outcast at school, Giovanni has just one friend: Campanella, the mayor's son. During the town's Festival of Stars, Giovanni begins to daydream atop a hill and looks up to see a steam engine train floating in the air. He boards the train, only to discover that his friend Campanella is already there. Thus, the two embark on their journey through the stars, where they encounter unusual people and visit many beautiful and haunting places.