The detective character in "Diablo!" is named Detective Dancer. Dancer was originally intended to be Chloe's surname before it was changed to Decker.
For the first time in three episodes (and, seemingly, thousands of Hell years), Lucifer changes clothes. Until then he was wearing the same suit, shoes, and pocket square as when he left.
This is a curiously clown-heavy episode. The opening scene is set in a killer clown hell loop, Ella wears a T-shirt with smiling clown face on it reading "Big Clown Energy", the season 1 episode five binder is titled "Insane Clown Pasties",- a nod to the famous Detroit Rap duo, ICP, Insane Clown Possie. The storyboards in the "¡Diablo!" writers' room lay out a case set at a clown convention.
Objects emblazoned with the Diablo logo in the Lucifer (2016) font are scattered over the set and production offices, and they resemble actual Lucifer-branded items given out to the cast and crew of the show.
At one point, Tom Ellis's accent slips through when he's using an American accent as Michael. His intrusive R (when the R sound is added to a word that doesn't have it) makes an appearance when Michael says "idea".