Act One
Siegmund collapses from exhaustion after taking refuge in an unfamiliar house. Sieglinde, startled to find a stranger in her home, tells him that her husband Hunding will return home shortly. Siegmund assures her that she has nothing to fear from an unarmed, wounded man. He tells her that his name is "Wehwalt" (Sorrowful) and rises to leave, but Sieglinde convinces him to stay and rest. When Hunding arrives, Siegmund relates the tragic tale of his life. Fighting a gang of ruffians who had killed his mother and kidnapped his twin sister, he became separated from his father. He was left alone, rejected by all he encountered and treated like an outcast. He had tried to rescue a girl who was being forced by her family to marry. Although Siegmund tried to shield her from her furious kinsmen, his weapons were shattered and the girl was killed. Hunding has, in fact, just returned from a search party he had joined with the girl's surviving family, hunting for Siegmund. He tells Siegmund that he may stay the night, but that they will fight to the death in the morning.

Left alone, Siegmund despairs at having no weapons to defend himself, even though his father had once promised him a sword in his hour of direst need. Sieglinde returns, having drugged her husband. She tells him how, during her wedding to Hunding, a stranger entered the house, which had been constructed around an ash tree. Clad in grey with a hat slung low over one of his eyes, he plunged a sword deep into the trunk of the tree; nobody has subsequently been able to pull it out. Sieglinde hopes that "Wehwalt" might be the one to seize the sword and free her from her unhappiness. Gazing intently at him, she realizes that he looks familiar; even his voice begins to stir her memory. When Siegmund tells her that his father's name was Wälse, Sieglinde excitedly recognizes him as her long lost twin. Siegmund triumphantly pulls the sword from the tree and, rejoicing in the reunion of the Wälsungs, hails Sieglinde as both sister and bride.

Act Two
The king of the gods, Wotan, urges Brünnhilde to protect his mortal son Siegmund in the coming fight. Brünnhilde is one of the nine Valkyries, immortal daughters of Wotan and the earth goddess Erda, who ride to battle in search of the bravest warriors. Wotan's wife Fricka arrives in a fury. As goddess of marriage, she is horrified at the incestuous and adulterous union of Siegmund and Sieglinde, and shamed by Wotan's own adultery. She demands that Hunding be avenged. Wotan is determined that Siegmund survive the fight so that he can win back an all-powerful ring forged from the Rhinegold. The ring had been stolen from Alberich by Wotan, but has come into the possession of the giant Fafner. By acting independently from his father, Siegmund would enable Wotan to circumvent his guilt for stealing the ring. Fricka points out that, by leaving a sword behind for his son, he has merely made Siegmund his unwitting player in his plan. Wotan reluctantly agrees that neither he nor Brünnhilde will protect Siegmund in the coming fight.

Alone with Brünnhilde, Wotan laments that the gods would be overthrown easily if Alberich were ever to regain the ring. Furthermore, Erda had foretold that the reign of the gods would end if Alberich were ever to have a son, and Wotan has heard that the dwarf has done so, after using his gold to entice a mortal woman. To Brünnhilde's shock, Wotan orders her to make certain that Hunding is victorious. Wotan's laws, carved onto his spear, must be upheld or Wotan's reign is meaningless.

Fleeing from Hunding, Siegmund and Sieglinde pause to rest. As Sieglinde sleeps, Brünnhilde appears, telling Siegmund that he must follow her to Valhalla. Siegmund refuses to leave his beloved behind. Moved by his passion, Brünnhilde determines to save Siegmund after all. When Hunding arrives, she shields Siegmund in the fight. Wotan then appears, shattering Siegmund's sword with his spear, and Hunding is now able to slay his rival easily. Brünnhilde, gathering up the broken sword, hurries Sieglinde away to safety. Wotan contemptuously kills Hunding, then vows to punish Brünnhilde for her disobedience.

Act Three
On a mountaintop, the Valkyries gather together before carrying slain warriors to Valhalla, where they will help guard the fortress of the gods. Brünnhilde soon joins them, fleeing from her father's wrath to protect Sieglinde. Unwilling to defy their father, the Valkyries refuse to help her. Sieglinde mourns the death of Siegmund, but Brünnhilde tells her that she must live for the sake of their unborn child, who will grow up to become the greatest of all heroes. Brünnhilde gives Sieglinde the pieces of Siegmund's broken sword, and tells her to seek shelter in the forest where Fafner guards his hoard, for Wotan would not dare to follow her there.

When Wotan arrives, he tells Brünnhilde that she must be stripped of her divinity, and left there in exile, locked in sleep, for any man to claim as his own. Brünnhilde tells him that although she disobeyed his orders, she knew that she was merely following what his heart desired most. Deeply moved by her courage, Wotan eventually agrees to Brünnhilde's one request, that he surround her with flames that only the bravest of men might penetrate. Wotan says his final farewell to his daughter. As she sinks into her long sleep, he calls upon Loge, the god of fire, to encircle the rock with terrifying flames; only one who knows no fear will be able to awaken her.

(Synopsis by Mark Lyons)