In 1929, Ivens went to the Soviet Union and was invited to direct a film on a topic of his own choosing which was the new industrial city of Magnitogorsk. Before commencing work, he returned to the Netherlands to make "Industrial Symphony" for Philips Electric which is considered to be a film of great technical beauty. He returned to the Soviet Union to make the film about Magnitogorsk, "Song of Heroes " in 1931 with music composed by Hanns Eisler. This was the first film on which Ivens and Eisler worked together. It was a propaganda film about this new industrial city where masses of laborers and communist youth worked for Stalin's Five Year Plan.