Inspired by Wagner’s own tortured affair with the wife of his patron, this searing masterwork is based on Arthurian legend and tells of an illicit romance between a Breton nobleman and the Irish princess betrothed to his uncle and king. The composer’s larger-than-life sensibilities are on full display throughout the score: Along with intoxicating orchestral music that surges in tandem with the couple’s burgeoning passion and a chord left symbolically unresolved until the last moments of the opera, the opera also features one of the repertory’s most soaring and ecstatic final climaxes, as Isolde surrenders to a love so powerful that she transcends life itself.