The John Graff murders shown in the show bare a striking resemblance to the John List murders which also occurred in Westfield but at 431 Hillside Ave instead of 657 Boulevard.
The title for this episode is German for "twilight of the gods" deriving from Germanic myth and legend about their ultimate destruction in a battle with the forces of evil.
Götterdämmerung: a collapse (as of a society or regime) marked by catastrophic violence and disorder.