Wagner's sense of what he wanted to do with the Ring drama changed by the time he returned to Siegfried. When he began the Ring, he had clearly seen Siegfried as the hero of the drama, but the desire to more fully explore Wotan's predicament impelled him to expand the project.
Siegfried and Mime quarrel, Siegfried demands that the sword Nothung be mended, but Mime cannot do so, much to his own chagrin – he wants to win the Ring back for himself. The Wanderer – a disguised Wotung tells Mime that Nothung can be forged only by one who has never known fear. This is Siegfried, and he repairs the sword himself, smashing the anvil as he leaves to reclaim the Ring. He arrives at Fafner’s lair and kills him. As he dies, Fafner warns that whoever put Siegfried up to this deed is plotting his death as well. From the The Forest Bird, Siegfried learns of the Nibelung hoard, the Tarnhelm and all-powerful Ring, and also of Brünnhilde, who sleeps on a fire-encircled rock - a bride who can be won only by a hero who knows no fear. Mime and Alberich (who had recognised the Wanderer and heeded his warning to fear Mime) quarrel over the spoils, withdrawing when Siegfried reappears carrying the Tarnhelm and the Ring. Mime tries to persuade Siegfried to take a cup of poisoned drink, and Siegfried kills him. Siegfried sets out to climb the mountain. He meets Wotan, who asks him about his exploits, but the youth splinters the Wanderer's spear with a single stroke of Nothung. Wotan, realises he is old and must go to Valhalla, but bequeaths the world to the redemptive power of Brünnhilde's love. Siegfried goes on to the top of the mountain where he discovers an armed, sleeping figure – the first woman he has ever seen. At last sensing fear, he summons the courage to kiss her. Brünnhilde, roused from her long slumber, realises that Siegfried has come. Throwing herself into Siegfried's arms, she bids farewell to Valhalla and abandons herself to human love.
This is the Schirmer edition of the Libretto in the original German with an English translation by Stewart Robb.