During the Nazi occupation of Poland, two Lvov sewer workers, Leopold Socha and Szczepek Wróblewski, drift from looting to a dangerous form of aid as they encounter Jews seeking escape from the ghetto’s brutal oversight. They first glimpse the brutality of the occupation when they witness Nazis executing Jewish women in the woods before returning to their routine. Back in Lvov, the Jewish residents endure persecution and humiliation at the hands of German SS men and the Ukrainian police, while underground an illicit barter economy and prostitution thrive near the ghetto walls, with smugglers like Mundek Margulies moving goods and stories of survival circling the crowded alleys.
As Socha and Szczepek work in the sewers, they encounter Jews attempting to slip from the Aryan side into Lvov’s shadowed underground, a vulnerable route through which hope flickers. Ignacy Chiger entrusts Socha with a watch and asks for help, a signal of payment in exchange for safety. Socha, wary but practical, agrees to hide the Chiger family—Paulina Chiger and her relatives—for money, while Szczepek remains cautious about the escalating risk. The offer is accepted, and the group turns the underground into a fragile shelter, testing the boundaries of loyalty and self-preservation.
The day’s routine is interrupted by a tense meeting at a tavern where Bortnik, a representative of the Ukrainian Auxiliary Police, extols the Nazis’ power. They press on with the dangerous task of sheltering people beneath the city while the ghetto’s liquidation looms. When the Nazis begin to empty the Lvov ghetto, panic ripples through the sewers as Paulina Chiger and the others flee deeper into hiding. Socha, Szczepek, Mundek Margulies, and Janek Grossman rally to organize an evacuation, even as personal loyalties and practical needs pull in different directions—Janek ultimately leaves his family for his mistress, Chai, intertwining love and risk in a city that offers little mercy.
Socha’s courage is tested when Ukrainian shooters capture him, yet a callous gesture of mercy from Bortnik ultimately frees him. He hides his secret involvement with the Jews from his wife, Wanda, even as the couple discusses the broader persecution and the moral weight of their actions. Wanda’s remark that “Jesus was Jewish” lands as a quiet provocation within Socha’s conscience, prompting him to reflect on identity, compassion, and complicity. A crucial turn arrives when Socha discovers that a shopkeeper knows about his actions, forcing him to confront the danger of exposure. He descends again into the sewer world and learns Mania is missing, a thread that deepens the sense of responsibility he feels toward the hidden families.
Negotiations among the hidden Jews intensify as the group debates how far Socha and his companions should go to keep them underground. The pressure from Bortnik grows sharper, and Socha initially compiles the truth about the information leak, but he later reveals the full secret to his wife during a tense dinner, sparking panic and eroding trust. The hidden Jews start to doubt Socha’s assurances, and Socha begins to question whether his loyalty should extend beyond the money they have accepted. The group’s cohesion unravels as Socha, disillusioned by the betrayals and the constant threat of discovery, decides not to take more payments and contemplates betraying them if Janek escapes. A heated dispute with Szczepek ripples through their fragile alliance, and the two men’s cooperative effort begins to fracture.
In a cold, harsh moment of resolve, Socha faces the most immediate danger when an SS man targets Mundek. With the aid of a Jewish smuggler, Socha manages to shoot the attacker, a decision that carries grave consequences: ten Poles, including Szczepek, are hanged for the death of the German soldier. The danger of exposure intensifies as a new accomplice is spotted near the shelter—someone who might betray them to save himself—and Socha acts quickly to move the Jews to safety under a church, attempting to preserve as many lives as possible. Chaja, who is pregnant with Janek’s child, joins the group, and she gives birth in the hidden space, but the baby suffocates to keep their presence a secret. Mundek and Socha later discover Janek and his companions dead, another brutal reminder of the cost of resistance and survival.
Socha agrees to smuggle Mundek to find Mania, hoping to reunite the group with more members who can share the burden, but they are shot by guards, and Mundek returns to the hideout with news of the tragedy. The winter gives way to spring, and a night of heavy rain floods the sewers just as Socha’s daughter prepares to celebrate her First Holy Communion. Socha races to rescue everyone still hidden below, while Bortnik’s suspicions sharpen, threatening to break the last threads of safety. Socha manages to escape the rising waters, but he loses consciousness in the flood. When he awakes, he finds Bortnik dead and finally emerges to the surface as Soviet forces enter Lvov, bringing a different kind of order to the city.
In the aftermath, the survivors—the Jews who had taken refuge and the few who managed to endure the collapse of the shelter system—emerge from the sewers as the city’s war-torn horizon shifts again. The narrative closes with the stark, sobering evidence of endurance, survival, and the human costs of moral choices made under extraordinary pressure. The final caption of the film leaves viewers with a lasting reflection on the price paid by those who risked everything to save others, and the complex web of loyalties that sustained a hidden community through one of history’s darkest chapters.
