Peripeteia

Once more I was a man in a myth, incapable of understanding it, but somehow aware that understanding it meant it must continue, however sinister its peripeteia.

Source: wiktionary

They were to bestride the Algerian scene like demigods until the tragic peripeteia of 1961 […]

Source: wiktionary

The visual moment whose consequences Freud began to ponder in the essay on the phallic stage has evolved into a peripeteia: "Some day or other it happens that the child whose own penis is such a proud possession obtains a sight of the genital parts of a little girl; he must then become convinced of the absence of a penis in a creature so like himeself. With this, however, the loss of his own penis becomes imaginable, and the threat of castration achieves its delayed effect."

Source: wiktionary