The film opens in October 1944, in the Auschwitz-Birkenau extermination camp. A small group of Sonderkommandos, prisoners assigned to dispose of the bodies of other dead prisoners, are plotting an insurrection that, they hope, will destroy at least one of the camp's four crematoria and gas chambers. They are receiving firearms from Polish people citizens in the nearby village and gunpowder from the UNIO munitions factory; the female prisoners who work in the UNIO are smuggling the powder to the men’s camp amid the bodies of their dead workers. When the women's activity is eventually discovered by the Germans they are savagely tortured, but they don't reveal the plot.