Fidelio work on the libretto by Georg Friedrich Treitschke. This version was first performed at the Kärntnertortheater on 23 May 1814, again under the title "Fidelio". The 17-year-old Franz Schubert was in the audience, having sold his school books to obtain a ticket. The increasingly deaf Beethoven led the performance, "assisted" by Michael Umlauf, who later performed the same task for Beethoven at the premiere of the Ninth Symphony. The role of Pizarro was taken by Johann Michael Vogl, who later became known for his collaborations with Schubert. This version of the opera was a great success, and "Fidelio" has been
Fidelio a rival nobleman, Pizarro. In revenge, Pizarro has secretly imprisoned Florestan in the prison over which he is governor. Simultaneously, Pizarro has spread false rumors about Florestan's death. The warden of the prison, Rocco, has a daughter, Marzelline, and an assistant, Jaquino, who is in love with Marzelline. The faithful wife of Florestan, Leonore, suspects that her husband is still alive. Disguised as a boy, under the alias "Fidelio", she gains employment working for Rocco. As the boy Fidelio, she earns the favor of her employer, Rocco, and also the affections of his daughter Marzelline, much to Jaquino's chagrin. On