When Harley confronts her past self she mentions her accent, a reference to Batman: The Animated Series (1992) where Harley Quinn was depicted with a heavy New York accent by her voice actor Arleen Sorkin.
The inside of Bruce's mind is meant to emulate Batman: The Animated Series (1992). Showrunners Justin Halpern and Patrick Schumacker revealed in interviews that they were able to use some of the actual backgrounds from the series and Jefferson Friedman, who used to work under Danny Elfman, interpolated some of Elfman's theme from the series into the score.
The episode contains homages to the comedy Frasier (1993):
- The intro and closing credits homage the show's own title sequences.
- Dr Psycho acts as a radio psychologist who takes calls from listeners.
- Harley mentions that she learned more of Psychology from watching the series.
Other than Bane, the callers on Dr. Psycho's podcast include Bizarro ("Feeling negative"), Maxwell Lord ("Tries to wish his problems away") and Gorilla Grodd ("Not handling divorce well").
At about the 20 minute mark when Harley hugs young Bruce the buildings in the background look like the Twin Towers/ World Trade Center.