Fidelio

Fidelio is an opera in two acts composed by Ludwig van Beethoven. It is Beethoven's only opera. The German libretto was originally written by Joseph Sonnleithner, then revised by Stephan von Breuning, and ultimately revised again by Georg Friedrich Treitschke.

Fidelio is considered a Singspiel, a German opera form that includes spoken dialogue in addition to musical numbers. The opera tells the story of Leonore, who disguises herself as a male prison guard named "Fidelio" to rescue her husband, Florestan, from political imprisonment and execution.

The plot deals with themes of justice, liberty, sacrifice, courage, and marital fidelity. Set in a Spanish prison, the opera portrays the struggle between good and evil, embodied in the contrast between the tyrannical prison governor Pizarro and the noble Leonore/Fidelio.

Fidelio underwent a long gestation period. The first version premiered in 1805 but was not well received. Beethoven revised it extensively, and a second version was performed in 1806, again without great success. The definitive third version, with Treitschke's libretto, premiered in 1814 to critical acclaim and has since become a staple of the operatic repertoire.

Notable musical numbers include Leonore's aria "Abscheulicher! Wo eilst du hin?", Florestan's aria "Gott! Welch Dunkel hier!", and the prisoner's chorus "O welche Lust." The four overtures written for the opera are known as Leonore Overture No. 1, Leonore Overture No. 2, Leonore Overture No. 3, and the Fidelio Overture. Of these, Leonore Overture No. 3 is often performed as a concert piece independently of the opera itself.