Todos menos Marco saben que su madre Anna se marcha mañana a Argentina a ganar dinero para la familia, ya que su padre Pietro, ha sufrido algunos contratiempos financieros. Hoy, la familia se va de picnic a las montañas. Los padres de Marco y Tonio, su hermano, están preocupados y no saben cómo darles la mala noticia a sus hijos. Cuando regresan de la excursión, Marco descubre el plan que tiene su madre a través de unos vecinos. Está tan triste que nadie consigue calmarlo. Al día siguiente, Anna trata de explicarle a su hijo lo dura que puede ser la vida, le dice que se porte bien y sube al barco que la llevará a Argentina.

A year has passed since Anna left. Marco thinks about becoming a postman after receiving a letter from her on the day his older brother visits home.

Marco sets out on his first job to deliver an urgent letter for Gina. A fun day at the beach begins when he finally returns in the afternoon.

Marco wants to work to help his mother come home sooner, but his father won't listen.

Emilio helps Marco get a job washing bottles after school. Marco's father Pietro buys him a world map and the two bond for the first time in a while.

Marco has an ominous dream about his mother, and he worries when there is no new letter from her.

Poor Marco can barely see the ocean from his new place. He goes from roof to roof to find a better view and meets Fiorina the puppeteer along the way.

Marco's monkey delights onlookers by dancing in the puppet show. Peppino the puppet master invites Marco to dinner to show his gratitude.

When Marco shows Pietro's friend the way to the hospital, he is touched to discover his father testing a new treatment on himself to save a patient.

Concetta goes out on the streets despite having a cold. Her symptoms worsen, but the family can't afford a doctor. Marco goes to the clinic for help.

Fiorina must put on a show alone because everyone else is ill. Just as she gets safely through it with Marco's help, bad news arrives about Anna.

Marco once again considers going to Argentina. Emilio asks Renato to help Marco get to Argentina after having huge success with his ice cream sales.

Joy over the group trip to Argentina is cut short when Renato goes back on his word. Marco gives Amedeo a letter for Anna and entrusts him to Peppino.

When Marco reveals that he'd meant to be on the ship to Argentina, Pietro begins laying the groundwork to go himself.

Marco is discovered by Leonardo, but the ship's head cook is impressed by his persistence. Pietro learns the extent of his son's determination.

The head cook is touched by Marco's love for his mother and takes him under his wing.

Marco grows fond of his new life aboard the ship.

The ship arrives in Rio de Janeiro. Marco's friends help him look for another ship headed to Buenos Aires.

The ship Marco boards in Rio is full of sick people and the meals are dismal. Marco meets a lost little boy named Nino aboard the crowded ship.

Six days after leaving Rio, the ship sustains heavy damage due to violent weather.

Marco begs for the ship to go faster after waking from a terrifying nightmare.

The ship finally arrives in Buenos Aires. The person who knows Anna's whereabouts has run away, and Marco loses all his money to a pickpocket.

Marco is at his wit's after losing all his money. Then he hears about a woman named Anna who has been taken to the hospital, and rushes to see her.

After being left with absolutely no information on his mother's whereabouts, Marco hears a rumor about a familiar puppet show in the area.

Peppino and his family decide to accompany Marco to Bahía Blanca.

The day has come to leave for Bahía Blanca.

Peppino has an idea to start a show based on Marco's life. Fiorina breaks down and cries for the real Marco during practice for her role as Marco.

Fiorina's heart breaks further as Peppino decides to write the death of Marco's mother into the puppet play to elicit more emotion.

Marco and his friends finally find shelter after running out of water. Gaucho Carlos revitalizes the group with hot food and wonderful music.

Marco and his friends are able to make their way to an inn after Carlos repairs their carriage.

Peppino and his troop stay the night in an abandoned place with a caved-in roof. Marco and Peppino decide to keep quiet about a harrowing encounter.

An Italian immigrant family suggests paying Mr. Moretti a visit for possible information on Marco's mother.

Marco visits Mr. Moretti soon after arriving in Bahía Blanca, but he provides no information on his mother or uncle's whereabouts.

Peppino's words have no effect on Marco. When Fiorina expresses her concern, Marco breaks down crying that his mother is probably already dead.

Marco meets a vagrant in town. After hearing his story, the man gives Marco a letter from his mother as well as new information on her whereabouts.

The news of his mother brings Marco's time with Fiorina closer toward its end. Marco starts working at a coal mine to cover his travel expenses.

Marco arrives in Buenos Aires, only to discover that his mother had already moved on to Córdoba.

Marco learns the deep extent of his mother's patience when he meets her cruel former employer before setting out to sail once again.

The captain becomes angry about Marco getting a free ride to Rosario, but changes his attitude upon discovering that Marco is a fellow Genoese.

Marco gets turned away at the door at the mansion in Rosario. Federico scrounges up enough money to cover Marco's train fare to Córdoba.

Marco strengthens his resolve to find his mother after his chance meeting with a woman and her children during the train ride to Córdoba.

Mequinez had moved long before Marco's arrival in Córdoba. In the town, Marco meets a boy named Pablo and develops a strange relationship with him.

To raise some money, Pablo looks for work in the fields. Unfortunately, the period is the wrong one and so he tries his luck fishing.

The house is not inhabited by the person Marco is looking for, but by an architect. The man, who appreciates the efforts of the little traveler, also offers him the money to travel to Tucuman.

The train attendants find Marco during an inspection and the boy ends up going down thirty kilometers from the destination.

During the journey, Marco falls ill for a few days and the herdsmen who take him with them must take care of his recovery.

After traveling for days, Marco leaves the group of herdsmen to get to Tucuman.

The journey to the village of Tucuman proves to be more hard than expected.

Having lost his donkey, Marco has to walk on foot.

Exhausted and under the snow, Marco is collected by a young man on horseback. On the way, a local elder has his nephew take him to Tucuman.

The long journey is over. The residence of the Mequinez is now visible and Marco reaches his mother.

After the recovery, Marco's mother can resume normal life. The Mequinez family, out of gratitude, gives the ticket to Genoa to both of them, with the promise of returning to Argentina.