Gotterdammerung

Ken Howard / Metropolitan Opera

The 2012-13 opera season has come and almost gone. For whatever wonders summer may hold, the Met Opera season of broadcasts closes this weekend with the living end, Richard Wagner's "Götterdämmerung."

In a staggering marathon of recapitulations, developments, plot changes and reversals, and a grand procession of leitmotivs that ignite a conflagration that ends the opera, the gods and the world are reborn in the cleansing fires of the overflowing Rhine.

But how does it all happen?