In September 1939, Władysław Szpilman, a Polish-Jewish pianist, is playing live on the radio in Warsaw when the station is bombed during Nazi Germany's invasion of Poland. Hoping for a quick victory, Szpilman rejoices with his family at home when he learns that Britain and France have declared war on Germany, but the promised aid does not come. Fighting lasts for just over a month, with both the German and Soviet armies invading Poland at the same time on different fronts. Warsaw becomes part of the Nazi-controlled General Government. Jews are soon prevented from working or owning businesses, and are also made to wear blue Star of David armbands.
By November 1940, Szpilman and his family are forced from their home into the isolated and overcrowded Warsaw Ghetto, where conditions only get worse, with food shortages leading to starvation, and the constant threat of SS brutality. Szpilman manages to find work by performing in a cafè frequently visited by upper-class Jews. On one occasion, he sees a young boy being savagely beaten by an SS guard while trying to crawl through a gap in the ghetto wall; the boy is dead by the time Szpilman is able to pull him through. On another occasion, Szpilman and his family witness the SS kill a family in an apartment across the street during a round-up, including throwing an elderly wheelchair-bound man from a window three stories high.
On 16 August 1942, Szpilman and his family are about to be transported to Treblinka extermination camp as part of Operation Reinhard. However, a friend in the Jewish Ghetto Police recognizes Szpilman at the Umschlagplatz and separates him from his family. He later becomes a slave labourer, and learns of a coming Jewish revolt. He helps the resistance by smuggling weapons into the ghetto hidden inside bags of food, on one occasion narrowly avoiding a suspicious guard. Szpilman eventually manages to escape, and goes into hiding with help from a non-Jewish friend, Andrzej Bogucki and his wife Janina, who provided him an apartment to hide.
In April 1943, Szpilman watches from his window as the Warsaw Ghetto Uprising, which he aided, unfolds, and then ultimately fails. After a neighbor discovers Szpilman and attempts to persecute him, he flees the apartment and meets his old friend Dorota and her husband, who provides him with another hiding place. The new apartment has a piano in it, but he is compelled to keep quiet since the apartment is located in a German area. Szpilman begins to starve and eventually suffers from jaundice after being abandoned by a member of the Polish resistance who previously supplied him food.
By August 1944, Szpilman recovers and witnesses the Warsaw Uprising taking place. The Home Army attacks the Schutzpolizei building across the street from the apartment, while Szpilman's hideout is destroyed by a German tank shell, forcing him to flee and hide in an abandoned hospital. Over the course of the following months, Warsaw is destroyed.
Upon noticing German troops burning the hospital with flamethrowers, Szpilman escapes and wanders through the ruins. He reaches an empty house where he finds a can of pickled cucumbers. While trying to open the can, Szpilman is discovered by Wehrmacht officer Wilm Hosenfeld, who learns that he is a pianist. He asks Szpilman to play on a grand piano in the house. The decrepit Szpilman manages to play Chopin's "Ballade No. 1". Hosenfeld lets him hide in the attic of the house, which is used as his center of operations, and supplies food for him.
In January 1945, the Germans are retreating from the Soviet offensive. Hosenfeld meets Szpilman for the last time, promising he will listen to him on Polish Radio after the war. Hosenfeld leaves Szpilman with a large supply of food and his greatcoat to keep warm. After Warsaw is liberated, Szpilman narrowly survives an ambush by People's Army troops who mistook him for a German.
In Spring 1945, former Nazi concentration camp inmates pass by a Soviet prisoner-of-war camp holding captured Wehrmacht soldiers and verbally abuse them; one lamenting over his former career as a violinist. Hosenfeld, being one of the prisoners, walks up to the violinist and asks if he knows Szpilman which he confirms and he requests Szpilman to rescue him. The violinist later brings Szpilman back to the site but it is abandoned.
After the war, Szpilman resumes his career at the Polish Radio, where he performs Chopin's "Grand Polonaise brillante" to a large prestigious audience. An epilogue notes that Szpilman died in 2000 at the age of 88, whereas Hosenfeld died in 1952, still in Soviet captivity.
