None of them was 20 yet. Zygmunt, Columbus, Jerzy, Malutki and Siwy form a small subversive group, which Zygmunt commands. One day, Zygmunt's section receives the order to move the secret printing house to a safe place. In the fight against the German military police patrol, Siwy is killed.
In the next combat action, Zygmunt's group liquidates the commander of the German railway guard station, known for the cruelty of bahnschutz Maltz. Columbus's girlfiend, Baśka, falls into the hands of the Gestapo; she is tortured, but she does not reveal Columbus's real place to live.
The Gestapo hits the trail of a secret radio station installed in Jerzy's apartment. All the service, except for Jerzy, who manages to play the role of the unconscious landlord, is arrested. Jerzy is suspected of collaborating with the Gestapo. He is threatened with a death sentence for treason. Thanks to the efforts of friends, the matter is clarified; completely rehabilitated, Jerzy returns to the underground group.
On August 1, 1944, the Warsaw Uprising broke out. Zygmunt, Jerzy, and Columbus fight on the barricades of heroic Warsaw. After the initial successes, they retreat under the pressure of the overwhelming enemy forces to the Old Town. Among the insurgents there are many fallen. One of the victims is Malutki.
The heroic defense of the Old Town is coming to an end. They have to break through to the city center at all costs. Wounded in the battle Columbus is a powerless witness to the tragedy. In a field hospital occupied by the Germans, Niteczka is raped and murdered.
