Die Walküre (The Valkyrie) is the second of the four operas in Richard Wagner’s Ring cycle, an epic of gods, monsters and humanity on a superhuman scale. Antonio Pappano, music director of The Royal Opera, conducts Keith Warner’s production. The singers include Nina Stemme as Brünnhilde and Stuart Skelton and Emily Magee as the twins Siegmund and Sieglinde. The opera features some of the most glorious music ever written, including the sparkling “Magic Fire Music” and, of course, “The Ride of the Valkyries.” In German with English subtitles. Anticipated running time is 290 minutes, including two intermissions.