According to The Hollywood Reporter that Warner Bros. DC's Joker standalone origin film is interested in bringing in Oscar winning actor Leonardo DiCaprio for non other than the Clown Prince of Crime Joker.
Sources say that the studio is going to use Martin Scorsese to try and lure the actor into the world of the DCEU. The report goes on to say that Scorsese's involvement could help to elevate the comic book genre in the hopes of creating more award-winning films like The Dark Knight.
As of now this is still purely speculation with Scorsese's deal not even finalized yet and even if it does, the chances of getting an actor of this caliber is still slim. Not to mention that this movie is supposed to be an origin film and yet DiCaprio is older than the current Joker Jared Leto. Only time will give clarity on this matter, stay tuned for more updates.