10 Things You Didn't Know About The Joker

8. His Girlfriend Was Originally A Cartoon Character

Harley Quinn has done the unthinkable: she's become almost as recognisable and beloved a member of Batman's rogues gallery as her beau, probably thanks to her appearances in the Arkham series of video games. She's since been spun off into her own series, is constantly rumoured to be appearing in the various live action films that have been made over the years, and has been paired up with Poison Ivy as much as she does The Joker. Despite being such an iconic character in the comic books, it's not actually where she originated.

Dr Harleen Quinzel first made her debut as The Joker's therapist-turned-girlfriend in the nineties Batman animated series (one of the best superhero cartoons of all time), with her ensuing popularity leading to an introduction in the comic book universe during the No Man's Land crossover. Which involved Gotham being rocked by earthquakes, getting cut off from the rest of the country, and The Joker running an entire corner of the city. Worked out pretty well for him, since he got a sweetheart out of the deal. And killed Jim Gordon's wife. Woops.