A young jewish boy, Solomon (Marco Hofschneider), is circumsized. Years later, on the day of his Bar Mitzvah, Kristallnacht occurs and his sister is killed. Solomon, his parents (Klaus Abramowsky & Michele Gleizer), and his two brothers Isaak (Rene Hofschneider) and David (Piotr Kozlowski) move to Lodz, Poland.
The Germans attack Poland. Solomon's father sends him and Isaak away in hopes that they will find someplace safe. Isaak and Solomon are separated. Solomon is rescued by Soviet soldiers and is sent to a Soviet orphanage in Grondo. Solomon becomes part of the Soviet Communist Union of Youth.
Germans attack the orphanage and as the orphans flee, Solomon is separated from them and later captured by German soldiers. Thanks to his fluent German, Solomon convinces the German soldiers that he is a German named Josef Peters. Solomon, now Josef (or Jupp) helps identify Stalin's son. Solomon is sent to aid Robert (Andre Wilms), a gay German soldier. Robert discovers Solomon is a Jew when he sees his circumcised penis. Robert promises to keep Solomons identity a secret. During a combat against the Soviets, Robert and two other German soldiers are killed, leaving Solomon by himself. Solomon then tries to surrender himself to the Soviet soldiers, but as he is walking across the battlefield other German soldiers command the Soviets to surrender. The Germans think Solomon is a hero and is sent to a Hitler Youth school.
On his way to the Hitler Youth School, Solomon and the woman he is with have sexual relations on the train. It is revealed that Solomon and Hitler share the same birthday. At the school, Solomon is introduced as a war hero and a true German. He is assigned to room with Gerd who becomes his best friend. Solomon also meets Leni (Julie Delpy), a German girl who he falls in love with but cannot have sexual relations with because that would give way his true identity. In class they measure Solomon's face for racial purity and he is labeled to be Aryan, although he is Jewish. A doctor pays his once a year visit to the school but when Solomon finds out the medical exam requires him to be naked he fakes a toothache in order to hide his circumcision.
Solomon and Leni have an argument in which Leni insults the jews and Solomon slaps her. Leni then calls him a limp dick and leaves. After not seeing Leni for months, Solomon visits her mother (Halina Labonarska) who tells Solomon Leni is pregnant with Gerd's baby. Solomon breaks down and confesses that he is Jewish. Leni's mom promises to keep his secret.
Once he goes back to the school, Solomon is called to the police station to clear up an issue dealing with his papers. The commander asks for Solomons Certificate of Purity. Solomon says it is still in Grondo, but the commander says he will ask for it to be brought to him. Solomon feels that he is doomed, for his lack of Certificate of Racial Purity will give away his Jewish identity. As he is leaving the building, it is bombed, and Gerd who was outside is killed.
The Hitler Youth students are sent to fight to defend Berlin. There Solomon surrenders to the Soviet army and tells them he is Jewish. The soldiers do not believe him and tell him that if he really were a Jew he would be dead or in a concentration camp. They have Solomon at gunpoint when Isaak, who has recently been rescued from a concentration camp, identifies him. Solomon and Isaak are released and go to Palestine which later becomes Israel.