This episode is a mutual nerd out over Jim Hensen's The Labyrinth.  This has been a lifelong love for Diana and Avalon and like all of those mutual topics, it leads to a lot of tangenting.  So get ready for puppets, David Bowie headcanons, sports metaphors, the morality of American Football, fae lore, and a surpringingly personal interlude sometime in the middle of the episode.