This curse, the Leitmotif of the whole story, began to operate at once.
The more subtle examples are inexhaustible in variety and resource; and perhaps the climax of subtlety is the almost entire absence of Leitmotif in the first scene of the third act of Gotterddmmerung, when Siegfried throws away his last chance of averting his doom.
Let us illustrate Wagner's mature use of Leitmotif by the theme which happens to be associated with Alberich's ring.
But we shall also find that, even if we could conceive the poetry to be a perfect expression of all that can be given in words and actions, the orchestra will express something greater; it will not run parallel with the poetry; the Leitmotif system will not be a collection of labels; the musical expression of singer and orchestra will not be a mere heightened resource of dramatic declamation.
A famous and typical instance of Wagner's use of Leitmotif in tragic irony is the passage where Hagen gives Siegfried friendly welcome, to the melody of the curse which Alberich pronounced on the ring and all who approached it.