Portrait of the French contemporary music composer of Hungarian origin Krystof MARATKA. In an interview filmed in Prague, he discusses his vision of music, the importance he gives to universality and the notion of imagination in music, his vision of creation and musical writing, the origins of his passion for music. He presents some of his works.The documentary consists of factual images, illustrative and synthetic images of planets and galaxies, extracts from concerts including "Hypnozy", "Le corbeau à quatre pieds", "Luminarium" and "Chant G' hai", extracts from an interview between the composer and Jean-Pierre DERRIEN on France Musique, the testimony of Krystof MARATKA from Prague and interviews with Hubert REEVES, astrophysicist and friend of Krystof MARATKA, Michel LETHIEC, clarinetist, professor at the National Conservatory of Music in Paris and Professor Mudr Zdenek MARATKA, Charles University in Prague, father of the composer.