The plot of this episode was the original idea for the first DCAU Batman movie, but it was felt that it worked better in the half-hour format. Instead, Batman: Mask of the Phantasm (1993) was made.
Janet Van Dorn is voiced by Stephanie Zimbalist, daughter of Efrem Zimbalist Jr., who voices Alfred.
The Riddler has no lines, but is seen presiding on the Arkham jury. When the Mad Hatter is about to announce the verdict, the Riddler has vanished. Interestingly though, when Batman and Janet Van Dorn attempt to escape the Asylum, Riddler's theme from his debut in If You're So Smart, Why Aren't You Rich? (1992) can be heard when Two Face and the inmates corner Batman and Janet Van Dorn. This may imply that the Riddler predicted Batman would escape, and left the proceeding early to be able to orchestrate a riot to stop Batman should he be able to escape. Seeing how strategic Edward Nygma can be, this is not unlikely of Riddler. It can be inferred that Riddler was apprehended when the GCPD stormed Arkham Asylum.
First time that a piece of Harley Quinn's origin is revealed. Janet Van Dorn says "Harleen Quinzel was a doctor here at Arkham."
This is the second time Batman is a prisoner in Arkham. The first was in Dreams in Darkness (1992) when he was temporarily institutionalized due to Scarecrow's fear drug.