The story
From the formulaic phrase riddle me this, additionally referring to the Batman comic book universe, in which the fictional supervillain the Riddler would pose puzzles for Batman to solve (riddle).
Etymology from Wiktionary, CC BY-SA 4.0.
riddle me that, Batman
Today it means: Said to demand that the listener take notice of a question or situation just mentioned, especially one that is particularly difficult to solve or explain. Full definition →