Martin Scorsese turned down the chance to direct 'Joker' because he didn't have the time to commit to the project.
It had been rumoured that the legendary 76-year-old director could helm the project about the genesis of Batman's greatest foe, who is played by Joaquin Phoenix, but ultimately he handed it over to Todd Phillips as he couldn't fit it into his schedule.
In an interview with the BBC, Scorsese said: "I know the film very well. I know (director Todd Phillips) very well. My producer Emma Tillinger Koskoff produced it. I thought about it a lot over the last four years and decided I did not have the time for it.
"It was personal reasons why I didn't get involved. But I know the script very well. It has a real energy and Joaquin. You have remarkable work."
'The Irishman' director also admitted that he was put off by the predictable narrative of 'Joker', which echoed his recent criticism of Marvel films, which he compared to "theme parks."
He said: "For me, ultimately, I don't know if I make the next step into this character developing into a comic book character.
"You follow? He develops into an abstraction. It doesn't mean it's bad art, it's just not for me ... The superhero films, as I've said, are another art form. They are not easy to make. There's a lot of very talented people doing good work and a lot of young people doing good work and a lot of young people really, really enjoy them."
'Joker' director Phillips, 48, recently revealed that Phoenix, 45, shared Scorsese's lack of interest in the comic book element of the film, which follows how stand-up comedian Arthur Fleck transforms into the villain.
In an interview with The New York Times newspaper, Phillips said: "(Joaquin) never liked saying the name Thomas Wayne. It would have been easier for him if the movie was called 'Arthur' and had nothing to do with any of that stuff."
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