<P> Harley Quinn first appeared in the Batman: The Animated Series episode "Joker's Favor", as what was originally supposed to be the animated equivalent of a walk - on role; a number of police officers were to be taken hostage by someone jumping out of a pop out cake, and it was decided that to have the Joker do so himself would be too bizarre, although he ended up doing it anyway . Dini thus created a female sidekick for the Joker, who would become his love interest . Arleen Sorkin, a former star of the soap opera Days of Our Lives, appeared in a dream sequence on that series in which she wore a jester costume; Dini used this scene as an inspiration for Quinn . Having been friends with Sorkin since college, he incorporated aspects of her personality into the character . Quinn was also inspired by a mutual female friend's "stormy but nonviolent relationship", according to Timm . </P> <P> The 1994 graphic novel The Batman Adventures: Mad Love recounts the character's origin story . Written and drawn by Dini and Timm, the comic book is told in the style and continuity of Batman: The Animated Series . It describes Dr. Harleen Frances Quinzel, PhD as an Arkham Asylum psychologist who falls in love with the Joker and becomes his accomplice and on - again, off - again girlfriend . The story received wide praise and won the Eisner and Harvey Awards for Best Single Issue Comic of the Year . The New Batman Adventures series adapted Mad Love as the episode of the same name in 1999 . It was the second "animated style" comic book adapted for the series, with the other being "Holiday Knights". </P> <P> Harleen becomes fascinated with the Joker while working at Arkham Asylum and volunteers to help treat him . She falls hopelessly in love with the Joker during their sessions, and she helps him escape from the asylum more than once . When Batman returns a badly injured Joker to Arkham, Harleen dons a jester costume to become Harley Quinn, the Joker's sidekick . The Joker frequently insults, ignores, hurts and even tries to kill Harley, but she always comes back to him, convinced that he truly loves her . </P> <P> After Batman: The Animated Series and The New Batman Adventures, Harley makes several other animated appearances . She appears as one of the four main female characters of the web cartoon Gotham Girls . She also made guest appearances in other cartoons within the DC animated universe, appearing alongside the Joker in the Justice League episode "Wild Cards" and alongside Poison Ivy in the Static Shock episode "Hard as Nails". </P>

What is the story of joker and harley quinn