Joaquin Phoenix wanted to make sure his version of the Joker "wasn't identifiable", as he wanted to create a character that psychiatrists couldn't define.
The 44-year-old actor is taking on the iconic role as Batman's most famous foe in the upcoming DC Comics origins story simply titled "Joker", and has said after being given the "freedom" to bring his own version of the character to life, he wanted to make sure the supervillain wasn't someone who could be "identified" by psychiatrists.
He said: "I wanted the freedom to create something that wasn't identifiable. This is a fictional character. I didn't want a psychiatrist to be able to identify the kind of person he was."
Joaquin was drawn to playing the villain - who has also been played by the likes of Heath Ledger and Jared Leto in previous movies - because of how "hard to define" he is, and says he didn't "refer to any past iteration" of the character when bringing his own version to life.