Georgi Dimitrov is on his way to Berlin, which is controlled by the Nazis. Hitler, Gyobbels and Gyoring plan the Reichstag fire. Van der Lube sets the Reichstag on fire. This triggers off a wave of arrests. The Communists have to go underground. Dimitrov is arrested. The German consul in Bulgaria refuses to receive his mother. She leaves for Germany. All over Europe, signatures are gathered in support of the detainees. At the court hearings, Dimitrov exposes the provocative policy of the Nazi government. Gyoring takes the witness stand. His speech on the grand future in store for Nazism is intermingled with actuality sequences from the World War II: victims, executions, death camps... Dimitrov is granted Soviet citizenship and leaves the fascist jail.