Brünnhilde, yield up the Ring, and end all the grief of the world!"
"The Ring?" wails Brünnhilde. "Knowest thou what 'tis to me? One flash of its fire outvalues all heaven's delight; for the gleam of that Ring is Siegfried's love!
"From love I never shall turn;
Of his love they never shall rob me,
Though into ruins
Valhalla's splendor should fall!"
Thus Brünnhilde refuses, and sends Waltraute away to take her defiance to Valhalla.
But retribution is swift, for on the moment Siegfried, changed to Gunther's shape by the Tarnhelm, comes and claims Brünnhilde as his bride. She resists and threatens him with the Ring. But now Siegfried, forgetful of the past, struggles for another with his own dear wife, overcomes her, and wrests the Ring from her. He then commands her to go into the cave, whither, after drawing his sword to lay between them as symbol of his loyalty to Gunther, he follows her.
The second act is outside the Gibichungs' hall. It is early morning of the next day. After a short scene in which the ever-plotting Alberich urges Hagen to get the Ring, Siegfried returns and tells Hagen and Gutrune of the winning of Brünnhilde and her approach with Gunther. Hagen calls together the vassals to welcome Gunther and his bride. The royal pair presently arrive and are received with loud acclaim. Straightway Brünnhilde recognizes Siegfried (who, however, does not know her) and, seeing the Ring on Siegfried's finger, she asks Gunther what he has done with the ring he took from her. His confusion reveals the truth to her, and she proclaims that she is wedded to Siegfried and not to Gunther. Siegfried swears on the point of Hagen's spear that her accusation is false. She repeats it, taking the same oath. Siegfried, Gutrune, and their vassals go out to prepare for the double wedding celebration; Gunther, Hagen, and Brünnhilde remaining solemnly condemn Siegfried to death for what seems treachery to one and all. Hagen, left alone, glories in the prospect of regaining the Ring.
The third act discloses an open place on the banks of the Rhine. The three Rhine-maidens pray to the sun for the return of the Rhine-gold. Siegfried, who has strayed from his companions on a hunting expedition, comes to the river bank. The maidens unsuccessfully attempt, by wiles and warnings of ill fate, to get the Ring from him, and finally swim away, foretelling his death that very day. Gunther, Hagen, and their vassals come to the place, and all sit down to rest. At Hagen's suggestion Siegfried relates the story of his life. But, lo! when he comes to the episode of his first passage through the fire, a draft given him by Hagen restores his memory, and innocently he tells of the waking and winning of Brünnhilde. All start up in amaze; Hagen stabs Siegfried in the back with his spear, and steals away. Siegfried falls, and after a few words sung to Brünnhilde, whom he sees as in a vision, he dies. His body is placed on a bier and borne away by the vassals with great pomp and state as the sun sets.
In the last scene we have the interior of the Gibichungs' hall as before. It is night. Gutrune comes from her chamber anxious for Siegfried. Presently Hagen's voice is heard calling for torches to light the returning hunters. He enters and, in reply to Gutrune's questions, tells her that Siegfried has been slain by a wild boar. Then come the vassals, bearing Siegfried's body. It is placed on a bier in the center of the hall. Hagen claims the Ring as his right for slaying Siegfried, but Gunther defies him to touch Gutrune's heritage. They fight and Gunther falls. As Hagen approaches the corpse to take the Ring, the dead Siegfried raises his arm threateningly. All start back in horror, and just then Brünnhilde enters and comes down to the bier. Here, after ordering a pyre to be built on the river bank, she sings a funeral song over Siegfried. The body, from which she has taken the Ring, is then placed on the pyre. Setting the Ring on her own finger, Brünnhilde calls on the Rhine-maidens to take it in turn from her ashes:
"Let fire, burning this hand
Cleanse, too, the Ring from its curse."