When Nello was two, his mother tragically died in the Ardennes, a region with vast forests that extends across four countries in Europe, mainly Belgium. After his mother's untimely death, Nello had no one who could take care of him, so his poor grandfather, named Jehan Daas, takes him in and takes care of him.
One day, Nello and his grandfather to take a walk through the town. On their walk, the come across a dog who was nearly beaten to death. They name the dog "Patrasche," and Jehan, who is an incredibly kind man, tends to the dog's health. In turn, Patrasche rebounds very quickly and returns to good health. And just as quicky, Patrasche and Nello become seemingly inseparable, spending what seems like every waking moment together.
When Jehan's nasty and nefarious landlord demands that he pay more money in rent or face eviction, Nello ventures out to become a milk salesman. In doing so, he hopes that he can earn enough money so that he and his grandfather can stay in the home they have stayed at for so long. Patrasche, the working dog that he is, helps Nello run his business and helps him transport his cart filled with milk each day.
While running his business, Nello falls in love with a girl named Aloise, who is the daughter of a well-off man who lives in Nello's village. That man is named Baas. And he wants what is best for his daughter. Thus, he strongly objects to his daughter associating herself with a poor man like Nello. In an effort to impress Baas, Nello enters into a drawing contest. The grand prize winner of the contest earns 200 Francs. Although the judges are impressed with Nello's drawing (his is illiterate but able to draw well), the panel selects another winner.
Later, a fire breaks out on Baas' property, and someone tells him that Nello was the one responsible for setting the fire. Accordingly, Baas forbids Nello from ever seeing his daughter again (even though he was not the one that set the fire).
Jehan dies and Nello and Patrasche are promptly evicted by their landlord. They become homeless and wander the streets of their village, hoping for a safe place to be in. One night, they find a cathedral that is putting on a play. They have no money and are thus not let in, but they return to the cathedral the next night to find no one inside. They spend the night at the cathedral but are found the next morning dead from hypothermia.
