Living in a tiny Swiss village, Romeo is a brave and soft-hearted boy residing with his kin. Tragically, he gains the attention of a man identified as "The God of Death" or Luini, notorious for procuring children and vending them as chimney sweepers in Milan. During his visit to the hamlet, Luini sets ablaze Romeo's family maize field with the intention of acquiring Romeo. With the crop lost and his father sustaining a head injury in a bid to douse the fire, Romeo selflessly sells himself to the God of Death to enable his family to retain a doctor. On his way to Milan, Romeo befriends a young chap named Alfredo Martini, who is later sold to another master. The duo pledges lifelong comradery and a promise to meet again. As a chimney sweep, Romeo encounters multiple difficulties and maltreatment, primarily from his new master's household and a gang named Wolf Pack. Nonetheless, upon reuniting with Alfredo, they establish a fraternity of sweeps called "The Black Brothers," aimed at opposing Wolf Pack and mutually aiding each other.