In the year 1943, Flyora and a fellow Belarusian boy stumble upon an abandoned SVT-40 rifle buried in a sandy trench, fueling their desire to join the Soviet partisan forces. Their defiance of the village elder, who cautions them that such actions might provoke the suspicions of the occupying Germans, leads to unforeseen consequences. Their activities are soon spotted by an Fw 189 reconnaissance aircraft overhead.
The following day, partisans arrive at Flyora's home to draft him into their ranks, much to his mother's distress. Initially, Flyora finds himself relegated to menial tasks as a junior militiaman. However, as the partisans move on, their commander, Kosach, instructs Flyora to stay behind at the camp, leaving him bitterly disappointed. Overwhelmed with emotion, he retreats into the forest, where he encounters Glasha, a young girl serving as a partisan nurse. Glasha, who is emotionally fragile, mocks Flyora’s attempts at maturity, expressing her desires for love and family, essentially taunting him with the notion that he isn’t truly alive.
Their fleeting moment of connection is shattered as the camp is suddenly ambushed by dive bombers and German paratroopers, which leaves Flyora partially deaf and drives them both into the depths of the forest. As they flee, they experience intense psychological breakdowns, alternating between catatonia and bursts of manic joy.
In a desperate attempt to find his family, Flyora leads Glasha to his village, only to discover it abandoned and infested with flies. In denial of their disappearance, he believes they are simply concealed nearby and races off across a bog. Glasha, turning her head at the wrong moment, stumbles upon the tragic scene of executed villagers behind his former home. The two characters succumb to hysteria after trudging through the bog, where Glasha implores Flyora to accept the grim reality of his family's death. Their turmoil culminates in a moment of aggression as Flyora pushes her into the water, though he quickly attempts to rescue her.
As fate would have it, Rubezh, a seasoned partisan fighter, finds them and brings them to the remaining villagers, where the village elder, scarred and burnt, relays the tragic news of Flyora's family's demise, reiterating his earlier warning against retrieving the rifles. Stricken by guilt, Flyora makes an attempt on his life by immersing his head in the bog, but he is rescued and consoled by Glasha and the villagers.
Later, Rubezh takes Flyora and two other men on a mission to raid an unsecured warehouse for supplies. Although Glasha promises to wait for Flyora's return, he is overwhelmed with despondency. The raid doesn’t go as planned; they encounter German troops guarding the warehouse, forcing them to retreat and resulting in the loss of the two companions to a landmine explosion. A subsequent attempt to steal a cow leads to further tragedy as Rubezh is shot, alongside the cow, by German machine gunners.
In another act of desperation, Flyora seeks to commandeer a horse and cart from a local man to transport the cow, but SS troops soon appear. The stranger persuades Flyora to conceal his gun and jacket, leading him to the village of Perekhody.
As Flyora is hurriedly briefed on a fabricated identity, an SS Einsatzkommando, flanked by collaborators from the Russian Liberation Army and the Belarusian Auxiliary Police, besieges the village. Flyora tries to alert the townsfolk of their impending doom, but he is forcibly herded into a barn church with the rest of the villagers. The Germans barricade the entrances, and an officer commands the villagers to climb out through a window, leaving their children behind. As Flyora and a young woman with a child try to escape, chaos ensues, with the woman’s child being thrown back into the church as she is dragged away, setting off a horrific chain of events with the German soldiers engaging in brutal violence. A chilling moment occurs when a German officer points a loaded pistol at Flyora's head for a photograph, before abandoning him amidst the smoke and flames of their destruction.
