Wagner's tetralogy Der Ring des Nibelungen concludes with Götterdämmerung. The composer's original draft, in which the gods are redeemed by the hero Siegfried's sacrifice, had fundamentally changed by 1874. Now in this 'cosmic catastrophe' Brünnhilde rides into Siegfried's funeral pyre, the Rhine overflows and Valhalla perishes, and the gods with it. It's the longest and most complex of the four music dramas, and it's orchestration is also the most colorful and sophisticated. Siegfried's Rhine Journey and Funeral March and Brünnhilde's immolation scene are some of Wagner's most potent theatrical moments and bring this drama to a shattering conclusion.