Phoenix is set to portray the DC Comics villain in a movie that is more moderately budgeted and darker than the studio’s other DC-based movies, known as the DC Cinematic Universe.

Phillips is directing from a script he co-wrote with Scott Silver (8 Mile, The Fighter). While plot details are largely unknown, the stand-alone is supposed to be set in Gotham City in the early 1980s.

If a deal is made, De Niro would play a talk show host who is somehow instrumental in the Joker’s origin.

The actor, known for his Oscar-winning work in The Godfather: Part 2 and Raging Bull, has also appeared in crime dramas and thrillers such as Goodfellas and Heat, as well as comedies such as the Meet the Parents series and Analyze This. While he has occasionally dipped a toe in fantastical or fantasy fare with The Adventures of Rocky and Bullwinkle and Stardust, he has eschewed the material and has certainly avoided comic book pics.

But the Joker project is being developed as no ordinary comic book movie. The budget is in the $55 million range, significantly lower than most comic book tentpoles that feature characters from Marvel or DC. And the stand-alone is said to be a character exploration as well as a drama, not a fight-fest.

Lensing is set to begin in September in New York.