The opera is divided into two acts. It is further divided into a prologue and sixteen scenes. Before each scene starts we hear a variation on the 'Screw' theme. This theme is based on twelve notes which are all the 12 notes in the octave. This is called twelve-tone row, but it is tonally based (the music is in traditional keys, unlike the music of Schoenberg). There are only 13 players in the orchestra.