At 17 minutes, Sherlock lists the ways the Midnight Ranger has died over the 80 years in publication. The last one he mentions, "my personal favorite: pushed over a waterfall [while] locked in the embrace of his nemesis". That is how the character Sherlock Holmes died with his nemesis Moriarty in the serialized adventures written by Arthur Conan Doyle. Death didn't stick for either Sherlock, though; this episode starts with Joan and Detective Bell reminiscing about Sherlock faking his death. In 1901 Conan Doyle was pressured by adoring fans to bring back the deceased detective in The Hound of the Baskervilles, elements of which this incarnation of Sherlock and Watson cover in Hounded (2016) and The Hound of the Cancer Cells (2014).
The title of the episode is a line from Superman (1978) and was said by Lois Lane to Superman when he caught her after she fell from a helicopter.
Eddie Eichorn says, "Any luck, this real Ranger mishegas will be squarely in our rear view mirror". "Mishegas" is a Yiddish word meaning "craziness" or "insanity".
All of the superheroes depicted in cardboard cut-outs as seen in the background, especially during Holmes and Watson's visits to Superlative comics, are actual comic book characters with different costumes or from different drafts. Among them are: Cyclops, Gambit, Jean Grey (Marvel Girl/Phoenix/Dark Phoenix), Magneto, Colossus, and Wolverine from the X-Men by Marvel Comics, as well as Green Arrow from DC Comics.
Detective Bell says that the Midnight Ranger's real name is Danny Dalton. This is in keeping with a standard comic book habit of having first and last names starting with the same initial. Peter Parker, Lois Lane, Doctor Doom/Victor Von Doom, Reed Richards, etc. This trend was largely started by Stan Lee, one-time editor of Marvel Comics and the creator or co-creator of the bulk of their golden age superhero characters (including three of the four listed above), who said alliterative names were easier to remember (he was having trouble keeping straight the sheer number of characters invented during his time).