First appearance of the Bat-Signal.
The episode is based on the August 1975 comic story from "Detective Comics" (Vol. 1) #450 titled, "The Cape and Cowl Death Trap!" also by Elliot S. Maggin.
In pre-production the original script was to have someone steal the cape and cowl and impersonate Batman while on a crime rampage.
Wormwood says that Batman "is only human after all," which is what one of the Joker's henchmen said in the Tim Burton's Batman (1989) film.
The moment where Batman discovers that Wormwood has escaped, causing him to emit an annoyed growl. Not only does his grumble come out so awkwardly it's impossible to take seriously, but with Batman only having a bandana covering his face at the moment it's led to many comments joking about him trying and failing to do his best pirate impression