"Phillips" film on the other hand, will dive deeper into the Joker's past and how he became the criminal mastermind fans know and love (to hate).
Though Warner Bros. had no comment regarding the casting rumours, sources revealed that Phillips met with Phoenix late past year and is waiting for the studio make a decision on who would follow Jared Leto as the modern-day Joker.
Phoenix is actually a great choice for the role as he is known for being a hardcore method actor who can sink into any character he plays.
The Walk the Line star is reportedly in talks for the lead role in the upcoming standalone Joker movie by The Hangover filmmaker Todd Phillips. They report that formal negotiations with the studio aren't yet underway, but that he is definitely on the top of the director's list. With the Joker standalone film, it looks like Warner Bros. finally have their man. Heath Ledger set a perhaps unsurpassable bar for Joker performances in Christopher Nolan's trilogy, yet Phoenix is bound to have a compelling take on the role.
The studio will allow interesting storytellers to plop these iconic characters into bold settings employing unique genres.
Scott Silver is co-writer on the film, which has been described as more of a gritty crime movie than a comic book one.
Phoenix has previously turned down the chance to play Lex Luther in Batman v Superman: Dawn of Justice.
He was nearly Doctor Strange, to the point where there were rumors he was going to be announced at SDCC until both parties went other directions.