An all-girl Catholic boarding school near Vienna for the wealthy Austrian elite and their children. The school is thriving, but faith is declining and the upper floors are de­ser­ted. The head of the institution, a young energetic nun, fights with ardor against this decline. Martha, 12, one of the nun’s favorite pupils, is a devoted girl who wishes to expiate the sins of the world. Encouraged by the nun, she is given a penance belt and taken to the abandoned upper floor.