Die Meistersinger von Nürnberg
Wagner’s operas have continuous music which develops is very logical ways using leitmotifs.  In the prelude we hear several tunes which are leitmotifs that are to be important during the opera: a theme that represents the dignity of the mastersingers, a theme for passion which later becomes Walther’s prize song, the chattering of the apprentices etc.  The music at the beginning of Act Three is also often played separately in the concert hall.