Harley Quinn was actually introduced in Batman: The Animated series, and later made the leap from screen to page due to her massive popularity. A few DC Comics characters have a similar origin story, but Harley stands out as having found the most success in the years which have followed. Sure, she may have started out as the Clown Prince of Crime's sidekick, but Harley now has her own series and a number of spinoffs to go with it, falling more into the anti-hero category rather than full on villain. Make no mistake about it though, this insane former psychiatrist is still just as twisted, and almost as sadistic, as her beloved puddin', The Joker.
