On one side are the students of St. Paul, on the other are the so-called Red Shirts, led by the aggressive, brutal, and intimidating Feri Áts.
After two members of the Red Shirts commit violence against the young Ernõ Nemecsek, the members of the Paul Street Gang, under the leadership of János Boka, decide that it's time to put an end to the Red Shirt provocations once and for all and to settle the question of who controls the construction site on Paul Street in a "final battle."
The Red Shirts are determined to take away the playground, known as the "Ground," from the boys of Paul Street and are not shy about their choice of weapons.
Although János' boys from Paul Street win the decision, little Nemecsek, who is "submerged" in the adjacent pond, catches pneumonia and eventually dies in his mother's arms.
In bitter realization that the fight for the "Ground" was completely in vain because the undeveloped piece of land is to be assigned a new purpose by the city and will never serve as a playground for any of the children again, everyone is left deeply affected.