It is May 8, 1945, the last day of World War II. The Nazis were ejected from Poland months before but the Soviets are asserting control. Two "cursed soldiers" of the anti-communist Polish Home Army, Maciek and Andrzej, have been sent to an unnamed town to assassinate the local Communist Party secretary, Szczuka. They ambush Szczuka's car and shoot him, then go into the town to report to a superior.
They find to their unpleasant surprise that they killed two random locals and Szczuka has arrived in town alive. Szczuka is there to attend a ceremony in honor of the new Communist mayor, Slomka. Maciek and Andrzej have an ace in the hole in the form of Drewnowski, Slomka's assistant, who is giving them inside information. The two men get a room in the same hotel as Szczuka and wait for a second chance. Meanwhile, Szczuka is looking for the son he hasn't seen for years (they were separated by the war), who is now seventeen and said to be serving in the Home Army.
Part of Wajda's loose war trilogy that included A Generation and Kanał. It is a remarkably subversive film, celebrating the anti-communist resistance of what was left of the Polish Home Army, made in 1958 during Communist rule in Poland.
- Chiaroscuro: Some arty black-and-white lighting in this movie, like a scene right at the end where the hotel clerk is unfurling a Polish flag early in the morning, in the shadowy lobby of the hotel, as light streams in through the open front door.
- Day of the Jackboot: Switching jackboots, as Soviet rule replaces Nazi rule in Poland.
- Downer Ending: Maciek dies and Poland is doomed to Soviet domination.
- The Dying Walk: After Maciek shoots Szczuka four times, Szczuka staggers forward a few steps, right into Maciek, who catches him and embraces him as he dies.
- Extremely Short Timespan: Two days, May 8-9, 1945.
- Great Offscreen War: Poland, struggling to recover after the massive devastation of World War II. Maciek and the doorman talk about Warsaw, recently razed to the ground by the Germans. Maciek and Krystyna talk in the ruins of a bombed-out church. Communist soldiers march through the streets.
- Heel–Face Door-Slam: Drewnowski tries to join the "cursed soldiers" at the end, only to get forcefully rejected by Andrzej, who gives him a few swift kicks to the ribs for good measure.
- La Résistance: Polish Home Army veterans fighting a guerilla war against the newly arrived Soviets.
- The Mole: Drewnowski is at the same time an ambitious career-minded Communist and a mole feeding intel to the Home Army.
- Mood Dissonance: Szczuka staggers into Maciek's arms and dies. Immediately after this, as Maciek is still holding him up, a fireworks display goes off, celebrating the appointment of the mayor.
- The Noun and the Noun: Ashes and Diamonds
- Oh, Crap!: Maciek jumps and nearly drops his newspaper when Szczuka identifies himself at the lobby and Maciek realizes they have failed in their mission.
- Significant Background Event: While Andrzej confidently reports on the hotel lobby phone that Szczuka is dead, Szczuka can be seen entering the front door behind him.
- Sunglasses at Night: Maciek, whose eyesight was damaged during the Warsaw Uprising.
- Title Drop: Maciek quotes from a patriotic poem by the Polish poet Norwid, about how the people fighting for a Polish homeland are like hemp burning into ash. The poet wonders "If only ashes will be left, and want chaos and tempest/Or will the ashes hold the glory of a starlike diamond/The Morning Star of everlasting triumph."
- To Absent Friends: As a woman softly sings "Czerwone Maki na Monte Cassino" in the background, Maciek and Andrzej commemorate their friends who fell in the Warsaw Uprising by lighting shots of vodka on fire, before downing the last two drinks themselves.
- White Shirt of Death: With a bedsheet instead. Maciek has just gotten shot by sentries. He dashes into an open area where a bunch of laundered bedsheets have been hung to dry. He clutches one to his chest as he hides and is surprised to see a billowing bloodstain on it.