Beethoven wrote one opera—Fidelio—though from its premiere in 1805 until its final revision in 1814 he called it Leonore. The story: Leonore attempts to save her husband, a political prisoner facing death, by disguising herself as the prison guard “Fidelio.” Bravery leads to liberty. “This music,” said the German conductor Wilhelm Furtwängler, “will always represent an appeal to our conscience.” Yannick Nézet-Séguin conducts a concert version with the Opéra de Montréal and the Orchestre Métropolitan. —L.J.