Erika Kohut (Huppert) lives in a state of high-strung discipline, trapped in a suffocatingly codependent relationship with her domineering mother. Outside their shared apartment, Erika is a cold, respected authority on Schubert and Schumann, yet she leads a secret life of voyeurism and masochism, frequenting porn shops and drive-in theaters.
Erika is a "failed" concert pianist teaching at a Vienna conservatory. She is cold and demanding with her students, maintaining a rigid veneer of autonomy. The Piano Teacher Lk21