Stefania is a Polish Jew put into the Warsaw Ghetto during WWII. Stefania is a city gal who believes the Germans are planning the end of the Jewish race. She fears for her life and the life of her two teenage sons.
Stefania meets a Jewish hospital employee, Fela Gorecki, who is a Polish Catholic woman involved in a Polish Underground smuggling operation. Fela and her associates arrange to have Jewish children smuggled out of the Warsaw Ghetto. Stefania makes arrangements for Fela to smuggle her sons out of Warsaw.
Paulina Tempel is a young and naïve Jew, country girl, and a farmer's wife. She is brought to Warsaw with her young son after the Germans killed her husband.
Paulina is assigned to live with Stefania and others in a Warsaw apartment. Stefania and Paulina realize they are very different, and they do not get along. Still, Stefania tries to persuade Paulina to smuggle out her son, Henryk. Paulina refuses, Henryk is all she has left in the world—except that Paulina is also pregnant. Stefania advises Paulina to hide her pregnancy.
When things worsen inside the Ghetto, Stefania takes matters into her own hands and kidnaps Henryk. She takes the boy to the Jewish hospital and pays Fela to smuggle him out of the Ghetto.
Paulina shows up but too late. She confronts Stefania but Fela intervenes. During a bombing, Fela manages to smuggle out Stefania and Paulina into the sewers underneath the city.
For the next few weeks, Stefania and Paulina live together in the sewers, behind a toilet in an Aryan home, and in the basement of another Aryan home. They struggle to get along—especially Paulina who has trouble getting past Stefania's kidnapping of Henryk.
While transferring to yet another location, the city of Warsaw gets bombed by the Germans. Stefania and Paulina manage to escape Warsaw by hitching a ride with a young German who works for the Polish Underground.
Once in the Polish countryside, the women have to survive on their own. After stopping in an abandoned farmhouse, they are discovered a young German soldier. Paulina shoots the German soldier, killing him. She then goes into labor. With Stefania's help, Paulina gives birth to a boy.
Yet, now they have to wander the countryside with a newborn. Luckily, they find work and a place to stay with a sympathetic Polish farmer and his wife. They pose as relatives of the couple.
Life begins to settle down until a German officer assigned to track escaped Jews visits them. The German officer does not believe their stories but he gets distracted by the Polish farmer's widowed brother. The brother convinces the officer that he knows the location of hidden Jews. He takes the German officer on a wild goose chase. The German officer kills the brother, but then continues his Jew-tracking away from the town.
The end of the war finally arrives. Stefania and Paulina reluctantly leave the farmer who saved their lives and return to Warsaw. They meet up with Fela and begin to the process of trying to locate their children. Stefania discovers that one of her sons died, and she cannot locate her other son. Paulina, however, is reunited with Henryk.
Stefania and Paulina are now like sisters. They not only overcame their differences, but they now fully trust each other. They vow to continue to search for Stefania's missing son and to help Fela reunite smuggled children with their families.
