So even though Heath Ledger’s Joker is incredibly popular, as long as the new version of Joker is different enough while still having a foot in the source material, Phoenix wouldn’t be worried about playing someone like The Joker, or any comic book character who’s already appeared on the big screen.
Joaquin Phoenix obviously still isn’t willing to divulge to the public if he will in fact play The Joker, but as he explained to Collider, an actor playing a comic book character who’s already been previously depicted is like how countless writers and artists create different versions of these same characters on the printed page over the decades.
However, Heath Ledger’s Joker in The Dark Knight has arguably become the most well-known portrayal of the character, and Ledger earned a posthumous Best Supporting Actor Oscar for his performance.
Plenty of actors have put their own spin on The Joker over the years, including Jack Nicholson in 1989’s Batman and Mark Hamill in various animated TV shows, video games, the list goes on.