Symphonie mixes fiction with reality. The author, Romain Schneid, tells the story of his own claustrophobia in front of the camera when, when he was 12 years old, hiding as a Jew during the German occupation, he could not leave a tiny apartment. He tells and he plays alone all the characters in his drama. He invents, deforms, imagines another end. He is at the same time the author, the narrator and the actor (the actors). Did he really experience what he's talking about, or did all that happen in his head? Are we facing a testimony or a delusion?