The "Annunciation of Death," a duet in Act 2 scene 4 of Wagner's Die Walküre, is a dramatic turning point in the Ring Cycle, as the warrior goddess Brünnhilde learns sympathy and love through encounter with Siegmund. My paper starts from the changing dramatic relationship between Brünnhilde and Siegmund over the course of the scene, and its reflection in the musical architecture. The dramatic narrative corresponds to a musical analysis based on rotational form in the use of the "Siegmund's Death Song" (Siegmunds Sterbegesang) motive, which is usually associated with Siegmund's downfall in leitmotivic nomenclature. However, instead of treating the motive as a fixed signifier for Siegmund, I focus on how realization of the motive and the resulting progressive momentum in the playing-out of the rotational form present a shift in which character holds narrative mastery.