 After WW II many young people arrive to Zagreb, among them a young worker Sonja Kacar. She is supposed to participate in the construction of the first generator in the Rade Koncar factory. Because there aren t enough experts and materials in Yugoslavia, the factory counts on help from fellow communist countries, Czechoslovakia and Soviet Union. However, after the Inform Bureau s resolution this help is no longer available. Sonja experiences a great intimate disappointment because Stjepan, who she is in love with, supports Stalin.