The Ring Cycle opens with this magnificent prelude.
The struggle for power and wealth in Das Rheingold irrevocably alters the order of the universe and determines the course of the entire saga.
In the depths of the Rhine, the three Rhinemaidens guard the Rhinegold, a treasure of immeasurable value. The Nibelung dwarf Alberich is dazzled first by the maidens and then by their treasure. Wellgunde reveals that whoever can forge the gold into a ring will gain mastery over the world. The required magic can be attained only by renouncing love. Alberich curses love vehemently and steals the gold.
Wotan, lord of the gods, dreams of eternal power and a fortress for the gods. He is reproached by his wife Fricka: he has promised to give Freia, keeper of the golden apples of eternal youth, to the giant brothers Fasolt and Fafner in return for their building the fortress. The giants demand their reward with Fafner proposing to abduct Freia by force. Loge, the god of fire, suggests an alternative payment: the mighty ring Alberich has forged from the Rhinegold. The giants agree to take Freia away as a provisional hostage until evening, and then hand her over in exchange for the gold. Wotan and Loge leave for the Nibelungs’ underground home, Nibelheim, to take possession of the gold.
Here they meet Alberich’s brother Mime, who has forged the Tarnhelm, a magic helmet that transforms its wearer into any shape. Alberich takes the helmet by force and uses his power to enslave the Nibelungs. Alberich appears and mocks the gods and dons the Tarnhelm to turn himself into a giant serpent, then into a toad, which the gods capture. Dragged to the surface, the dwarf is forced to summon the Nibelungs to heap up the gold. Wotan wrests the ring from his finger. Shattered, Alberich curses the ring: no one who possesses the ring will escape death.
The giants return and agree to accept the gold but Wotan refuses to part with the ring. Erda, goddess of the earth, appears and warns him that possession of it will bring about the end of the gods. Wotan reluctantly gives the ring to the giants and Freia is freed. The gods witness the first effects of the cursed ring as it claims its first victim – the killing of Fasolt by Fafner in the ensuing struggle over the treasure. The voices of the Rhinemaidens are heard, lamenting the loss of their gold as the gods walk toward their new home, Valhalla.