It's written by Eugenie Ross-Leming and Brad Buckner and takes place in this parking lot in Detroit, home to the cheeriest 666 you ever did see:
Because, like Lucifer always said, IT HAPPENS IN DETROIT.
Other things this episode contains:
- callback to 8x19 "Taxi Driver," which perhaps you could have guessed from the title
- the title is also the title of that "paved paradise and put up a parking lot" song, which--who knew that was the title of that song? I sure didn't.
- the "paved paradise" lyrics are relevant because Heaven is sort of fucked, because they already couldn't keep the lights on even BEFORE Castiel killed whatsername (and Hell is also fucked, because they lost all their souls)
- this parking lot is some kind of weird celestial parking lot that can be driven to (in Detroit), but also deserves as a portal to both Heaven and Hell--and, in times of extreme duress, perhaps the Empty(??!?!)
- 8x19 is relevant because that's the episode where we learned reapers are warped pseudoangels who have the ability to ferry people to Purgatory (and perhaps... other dimensions of this universe?)
- And, as Billie says, "We need to talk."
- episode serves to shift attention back to Billie, the Empty guy, Jack, and Lucifer in the Empty just in time for the mid-season finale