"I always wanted Joaquin Phoenix for Batman"
While plugging the release of his new movie mother! to Yahoo, Darren Aronofsky dropped this interesting bit of casting trivia, which has us wondering what might have been. The Walk the Line star has traditionally eschewed blockbustersin favor of smaller, more cerebral features, but the thought of him playing Batman is intriguing. Around the time Aronofsky started working on his Batman: Year One movie, Phoenix had appeared in Gladiator, so moving from ancient Rome to donning the cape and cowl would have been an interesting shift. This also isn't the first superhero that Phoenix has been associated with, as he was in talks to play Stephen Strange in Marvel's Doctor Strange movie, but that role eventually to Benedict Cumberbatch.
Several years after Batman & Robin's release, Warner Bros approached Darren Aronosfky about rebooting the Batman film series with Batman: Year One after he had initially pitched a cinematic version of The Dark Knight Returns, another Frank Miller tale. However, while all the theatrically-released Batman movies so far have been mostly faithful adaptations, Aronofsky's Batman: Year One would have taken significant creative liberties with the Dark Knight's mythology, such as giving it a Taxi Driver-like tone and turning the Batmobile into a Lincoln Continental with two bus engines. Perhaps a weird superhero movie like that would have better appealed to Joaquin Phoenix's creative sensibilities.
In the end, Warner Bros decided that Darren Aronofsky's Batman: Year One movie was scrapped, though the studio was still keen on providing a fresh take on the Batman mythos. That ended up being Batman Begins, and the rest is history