Down-on-his-luck, dumpster-diving Metatron (Curtis Armstrong) suddenly finds himself transported to a bar for a meeting with Chuck Shurley aka Carver Edlund (Rob Benedict), who - to nobody's great surprise - reveals himself to actually be God.
Chuck has been working on his autobiography and wants Metatron to be his editor.
Meanwhile, back on Earth, Sam and Dean investigate an unexplained suicide in a town called Hope Springs, and soon discover that Amara's zombifying fog is the cause.
There are two very distinct strands to Don't Call Me Shurley and while the Winchesters and the fog storyline is largely quite pedestrian, up until the last stand, the two-hander between Chuck and Metatron is sublime, veering from straight-up comedy to well-observed musings about the state of the universe.
Robbie Thompson's script manages to nicely balance wit with pop philosophy, confronting serious issues without getting too heavy or forgetting that ultimately Supernatural is a pulp horror show.
Chuck has bobbed in and out of the Winchesters' life since it was revealed, back in season four, that he was the author of the Supernatural novels, chronicling - and predicting - their adventures, and after a while - although labelled a Prophet Of The Lord - it was quite obvious he was rather more than that.
Given the belief that "we" were supposedly made in his image, it seems only right for him to have suffered from all-too-human frailties, such as loneliness (that presumably he coded into our make-up).
As well as the verbal repartee between Chuck and Metatron, there were some nice visual Easter eggs as well (I particularly dug Chuck's "World's Best Dad" mug), and the episode addressed the "feud" between Amara and her brother (he creates, she destroys), as well as the more general question of "where have you been?"