The story of the liquidation unit of the Home Army Counterintelligence Section. The action centres on the lives of two commanders, Leszek Zaremba (a.k.a "Onyks") and Tadeusz Korzeniewski (a.k.a "Dager"). The first one is dutiful and calm. He handles his tasks precisely and effectively but with each passing day, he has more doubts whether his actions are moral and the feeling of remorse does not let him fall asleep. The second character, on the contrary, has different feelings. A desire for revenge against the Germans is fueling his motivation. In his opinion, the cruelty of crimes committed by the Nazis allows him to use evil in the name of higher purposes.