Trivia / Batman: The Animated Series E22 "Joker's Favor"

• Actor-Inspired Element: Harley Quinn was based on Calliope Jones, Arleen Sorkin's character on Days of Our Lives, specifically when she was a jester in a fantasy sequence. Paul Dini, who was friends with Sorkin, was shocked she still talked to him.
• First Appearance: The first time Harley Quinn appeared in any medium. Rocco and Henshaw, a pair of goons often seen helping the Joker out in various episodes, also make their debuts here.
• Referenced by...: Suicide Squad (2016). The Joker's speech is written on Harley's bat.
• What Could Have Been: More like a case of "what might not have been". The whole reason Harley Quinn was designed for this episode (designed at all, for that matter) was because, at first, the writers thought having the Joker jump out of the cake himself would be silly (even though that's how it actually went in the final draft) so they designed a Perky Female Minion with the intention of her doing that job. She may never have done the role she was designed for, but several episodes of Character Development later, Harley had become a vital part of the Batman mythos.

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