The coolest nuttiest Gotham girl.
Age: In her 20's
Hair colour: Blonde
eye colour: Blue
Role: Use to be a doctor at Arkham but is now the Joker's sidekick/ girlfriend.
Enemies: Any enemy of the Joker is her enemy
Friends: poison Ivy.
Harley Quinn started off in the Comics of batman but soon crept into the animated series of batman and even made an appearance on the superman animated series with the joker.
Her appearance later changes in the Batman game 'Arkham asylum' wearing a nurse style costume with purple and red instead of her classic black and red.
In the Arkham city game she is seen as more of a biker girl with red and black tips on her blonde pigtails.
She never appears on any of the Batman movies but there was a rumour floating around the the Batman and Robin film was suppose to be a film about Harley Quinn and batman after the joker's death but she would be betrayed as the Joker daughter seeking revenge for her father's death. This idea was soon unfortunately scraped and Batman and robin was made instead.
Harley Quinn movie poster
Harley Quinn's original appearance
This is how she appears in the animated series and the comics.