The fire started by Luini devastates the only cornfield that Romeo's family has left. Romeo's family rush to the field to try to save the domestic animals, but Roberto injures his head while leaping out of the flames. After this tragic incident, Roberto's injury worsens and a rumor about Roberto intending to sell Romeo to the god of death spreads in the village. Then, after an argument with his father, Romeo runs away from home and hides in Anita's barn, where he hears that Roberto is not his real father. Meanwhile, Luini approaches Roberto and pressures him to sell his son.

After being treated by doctor Baresi, Roberto will recover and will not go blind. Romeo has sacrificed himself for the sake of his family and must now leave the village. On his way to Milan, Luini tells Romeo to go to the town of Locarno and wait for him there. Along the way, Romeo is mistaken for an apple thief, but is saved by Alfredo, a boy who is also heading to Milan to become a chimney sweep as Romeo. In Locarno, Alfredo's bag falls into a river after being stolen, so Romeo throws himself into the river to recover it.

In Milan, Romeo and Alfredo are sold as chimney sweeps to different bosses, having to separate, but not before swearing eternal friendship. Romeo is taken by Rossi, his buyer, to his house, where he will start a new life.

Romeo goes to clean Professor Casella's fireplace who, to thank him, gives him an illustrated book. However, Romeo cannot read, so the teacher offers to teach him to write his name. Upon his return home, he finds a letter left by the girl who lives in the same house, Angeletta. But, how will Romeo know interpret what is written on it?

Romeo finds Anselmo lying on the street and covered in bruises. Anselmo tells Romeo that he confronted Tachioni because he hates outsiders and wants to kick Romeo out of town. Romeo, full of rage, runs in search of Tachioni.

The carriage Romeo has sneaked into contains explosives that the robbers intend to use to blow up the police station and free their imprisoned friend.

After a long time, Romeo and Alfredo finally reunited and joined other young chimney sweeps to form the Black Brothers fraternity with Alfredo in command to confront the Wolf Pack. Romeo tries harder to learn to read inspired by Alfredo. Knowing that Alfredo only has one book and that it is in poor condition, Romeo introduces him to Professor Casella, who offers him to choose a book. Alfredo borrows one from Voltaire dealing with freedom and equality.

As retaliation for losing the fight at San Babila church, Michaelo was kidnapped by the Wolf Pack. To release him, their leader Giovanni demands that the Black Brothers hand over Alfredo to them. Alfredo decides to show up alone, but Romeo doesn't want to leave him alone and offers to go with him. A new battle between the two gangs is approaching.

Romeo and Angeletta meet the old puppeteer Teo and little Nana. Teo has a sad secret: Leon, his son, left him and his granddaughter after a quarrel. He would rather be a doctor than a puppeteer. Now Teo wishes nothing more than to see his son again. Angeletta asks Romeo and the Black Brothers to find Leon. Also, Matteo is about to reveal a secret about Angeletta to Romeo while talking with Rossi.

Angeletta's greatest wish is to meet her grandmother, the Countess Isabella Montovani, before her serious illness progresses. The Black Brothers therefore drive Angeletta to the castle in a wooden cart. Rejected by the security guard, they climb over the wall. They are discovered and there is a chase in the castle courtyard.

In Milan, a wedding of the nobility is taking place and all rich and noble people of the area are invited. Even the king of Italy is expected to come. Then Romeo accidentally meets Bianca, Alfredo's sister who was believed to be missing. When he conveys the good news to him, he learns Alfredo's mysterious story.

Professor Casella discovers that Alfredo's illness is worse than initially thought. Alfredo also knows that he will not live much longer. Nevertheless, he firmly intends of showing up before the King of Italy with his sister Bianca to expose his aunt and uncle by showing the king the authentic royal insignia. To achieve this, he thinks up a plan with the help of the Black Brothers to sneak into the duke's wedding banquet.

Alfredo and Bianca are still trying to show in front of the King of Italy and expose the damage that has been done to their family. The Wolf Pack has temporarily allied with the Black Brothers and they help carry out this plan together. They have to deal with the bodyguards of Alfredo's uncle so that Alfredo and his sister can sneak into the banquet.

Romeo suffers greatly from the sudden death of his friend Alfredo. He sinks into a deep sadness and distances himself more and more from reality. The Black Brothers try to cheer Romeo up again. But even when Dante tries to force him come to his senses, Romeo remains withdrawn.