Joker (Earth-1: Post-Crisis)

"Gotham City and me, we just... Have a bad history with freaks dressed like clowns."

- Bruce Wayne

An unnamed man known only as The Joker is an infamously brutal criminal from Gotham City.

Murder of Robin
Around 2005, Joker has a run in with Batman's partner Robin. He murders the latter and paints on his chest piece the words "HAHAHA! Joke's on you, Batman!". Enraged, Batman knocks Joker's teeth out and places him in Arkham Asylum.

Arkham Asylum
In Arkham Asylum, Joker gets metal fillings for his teeth and tattoos the word "Damaged" on his forehead as a message for Batman.

DC Extended Universe

 * (indirectly mentioned)
 * (flashbacks)
 * (flashbacks)

Trivia

 * This is the only live action version of the Joker to have short hair.