Plot

The young daughter of an army captain missing in action runs away from school and is kidnapped by Parisian lowlifes. When the kidnapper flees to Nice with the child, the kind-hearted employee of one of his accomplices sets off in pursuit.

A series of misfortunes befalls young Marie-Laure. Her army captain father goes missing in action, her mother dies of grief, her guardian is called away to war and she is sent to a harsh boarding school. She runs away and is kidnapped by Le Bachelier, a Parisian lowlife. Left to be treated as a slave in the house of a drunken cobbler, she's befriended by Bosco, the cobbler's teenage hunchback employee. Then her father returns unexpectedly, and Le Bachelier extracts a ransom with no intention of setting the girl free. With the police closing in, he flees with Marie-Laure to Nice, but kind-hearted Bosco sets off in pursuit—Des de Moor

Part One: Marie-Laure

Pierre de Valen, a Captain in the French military, and his wife Marie, along with Pierre's brother Jacques watch the couple's young daughter Marie-Laure dance to a popular song at their Bel-Abri villa.

Pierre receives a letter, summoning him to Casablanca where he will take command of a Colonial Infantry battalion. Jacques promises to watch over Marie and Marie-Laure for his brother.

Pierre boards a ship in Marseilles, wishing his family a goodbye. Marie and Marie-Laure pray each night for Pierre's safe return.

Pierre is able to write to his family, reporting that they have seen no action but are anxious to begin. He also sends a photo of himself in uniform. Marie-Laure goes to bed hugging the photo.

Jacques shows Marie a newspaper article reporting that troops currently stationed in Morocco are being called home after defeating the German backed insurrectionists.

However, Pierre's battalion is then attacked by the rebels. He takes up arms himself in the fighting before ordering the battalion to the front gate as the rebels break through.

Jacques receives word from the Ministry of War of the attack and of Pierre's death. His body was not recovered. Marie is distraught after learning of Pierre's death and falls ill. She asks Jacques to care for Marie-Laure before dying.

Marie-Laure mourns the loss of her parents. Jacques, a Lieutenant in the Navy, is summoned by the Naval Ministry to a post in the Far East. Marie-Laure is sent to the Molière Boarding School with reports being sent to Jacques.

Marie-Laure is brought to the school by her maid Marion, who she shares an emotional goodbye with. She struggles to adapt to life at Molière, facing teasing and bullying from the students as well as harsh treatment from her teacher who falsely accuses her of disrupting the class and misbehaving.

That night Marie-Laure escapes from the boarding school. She falls asleep on the side of a pathway where she is robbed. The man leaves but returns and kidnaps Marie-Laure.

Part Two: The Graduate- "The Graduate"

Marie-Laure is brought into a flat where two cobblers are at work. The older of the two, Tiron, sends the younger, Bosco, away so he can speak to "the Graduate," alone. Bosco eavesdrops on the conversation and hears The Graduate give the cobbler a down payment with a promise of more if he handles it well. The Graduate leaves Marie-Laure with the two.

She is brought to bed by Bosco who acts protectively towards her. Marie-Laure is forced to work for the drunk Tiron who treats her cruelly. While Tiron is passed out drunk, Bosco crafts a toy for Marie-Laure to play with. He provides her with a meal once Tiron leaves.

One year later her missing persons case is closed by the police. Marion is furious and blames the Molière School is responsible for her disappearance though the School is found innocent of all blame.

Marion receives a telegram from Pierre. He was not killed in the battle but captured by the rebels. After a year of captivity, he escaped with the help of a local Moroccan women and sailed to Tangier to learn of Marie's death.

Pierre returns to Paris as a hero and given a large parade. Shortly after his arrival he is informed of Marie-Laure's disappearance. He shoos the dignitaries away and grieves with Marion.

Part Three: The Pirates of Paris

Pierre begins a media campaign to find Marie-Laure. Printing her picture in the newspaper and calling on the people of Paris to help find her. The news spreads through Paris. The Graduate sees the picture and sends a letter to Pierre.

The letter claims to know where Marie-Laure is but requests that Pierre not involve the police and invites him to meet the next evening at 10 PM. The Graduate signs the letter as "A Friend."

Pierre arrives at the Quai d'Orléans, the designated meeting location. He is met there by one of The Graduate's people and is taken to gang's headquarters. The Graduate requests 50,000 francs in-exchange for Marie-Laure. Pierre agrees to the offer and signs a check over.

The Graduate arrives at Tiron's to collect Marie-Laure for the trade. Bosco attempts to stop the exchange from happening, but Marie-Laure is taken away Tiron is paid 500 francs for her. Bosco is troubled by Marie-Laure's cries as she was being taken away.

He leaves Tiron's flat and follows The Graduate and Marie-Laure. Bosco follows them to the headquarters where The Graduate's gang is trying to convince The Graduate to sell Marie-Laure for a higher ransom. Bosco rushes to the police.

The Graduate uses the Marie-Laure to attempt to renegotiate with Pierre, requesting another 50,000 francs. After seeing her Pierre agrees but Marie-Laure is taken away and Pierre is taken captive as well. He is told he'll be set free once the checks cash. The cops raid the headquarters taking many members of the gang captive and releasing Pierre, though The Graduate escapes with Marie-Laure.

Bosco decides to conduct his own investigation after the police have no leads. While searching around the gang's headquarters, Bosco notices a trap door and discovers The Graduate's escape route.

Following The Graduate's footsteps he discovers The Graduate's safe house. Searching through the jackets left in the safe house, Bosco finds an envelope addressed to Edmond Talmin.

Part Four: Bosco's Journey

Bosco goes to the address and notices a car leaving he residence. Bosco leaps onto the back of the car, which does contain both The Graduate and Marie-Laure. The two depart the car at the train station and board a train to Nice. Bosco sneaks on the train through the luggage hold.

In Nice, Bosco tails The Graduate into the city but loses track of him. Bosco continues to search throughout the day but fails to find any information.

The next morning, he is found exhausted on a bench and given a coin by two wealthy women who believe him to be homeless. He gives the coin back to them telling them he is not a beggar but instead they find him endearing and give him more money.

Bosco uses the money to buy a suit and rent a room at the Hotel Suisse. He writes a message to the Pierre and the police informing them of The Graduate's location in Nice.

Part Five: Villa Carmen

Bosco notices the carriage and horse that The Graduate and Marie-Laure were in when he lost their trail. He pays the carriage driver to take him to the place that he dropped them off at, which turns out to be Villa Carmen.

That night, while The Graduate prepares for a night at the casino with the ransom money, Bosco sneaks into the Villa and escapes with Marie-Laure. Returning with her to the Hotel Suisse, he receives a message from Pierre expressing gratitude and his plans to come to Nice the next day.

Bosco goes to the Nice police who were tipped off that he may arrive with information. The Graduate returns to the Villa and discovers that Marie-Laure has been taken. Realizing the police may be arriving, The Graduate attempts to sneak out of the Villa but is caught by Bosco.

The two engage in a scuffle, including some gun shots, before The Graduate is arrested by the police.

Bosco meets Pierre at the train station and informs him of the good news. Pierre is reunited with Marie-Laure at the Hotel Suisse. He embraces both Marie-Laure and Bosco, later adopting Bosco. Under Pierre's care, Bosco trains to become a lawyer and helps raise Marie-Laure.