Throughout the Ring cycle, Wagner uses a system of musical themes, or leitmotifs, associated with characters, events, emotions, and things. The entire first act of Die Walküre depicts the experience of falling in love in one great arc, from initial attraction to consummation. It is one of the theater’s most convincing portrayals of the power of love—even if the lovers in question are in fact twin brother and sister. Act III opens with the famous Ride of the Valkyries. In a dramatic masterstroke, Wagner uses the sound of eight powerful female voices, punctuated by shrieking laughter, to depict the terrible thrill of combat. The opera ends with some of the most moving music ever composed, as Wotan intones his farewell to Brünnhilde.