Romeo is an 11-year-old boy, who lives with his family in poverty in a small village in Switzerland. One day, Romeo decides to sell himself into slavery, because the money will enable his sick father to get the medical treatment he needs. An evil man named Ruini pays money for Romeo and takes him far away to Milan. Romeo is forced to become a chimney sweep. His life in Milan is hard, and his master's family is always hard on him, but he also has a lot of good times with his best friend Alfred and the other chimney boys. Romeo and the chimney boys organize a group of chimney sweeps which they call the "Black Brothers".