An unlikely report surfaced in 2017 about Batman's arch-nemesis The Joker starring in his own film, separate from the existing series of DC Comics films, with Martin Scorsese on board as a producer and Leonardo DiCaprio in line to star.

Well, it might not be DiCaprio, but another acclaimed actor has reportedly been in talks to take on the role played previously by Jack Nicholson and Heath Ledger, as well as Jared Leto in 2016's Suicide Squad.

According to Variety, Inherent Vice and Walk the Line star Joaquin Phoenix has agreed to play the Clown Prince of Crime.

The proposed origin story will exist in a separate continuity strand to Suicide Squad and other DC Extended Universe films such as Justice League and Wonder Woman in a new series of standalone stories.

These films are intended to "expand the canon of the iconic comic-book characters with unique story angles that aren't included in its current cinematic universe," said Variety.

Sources have indicated that the film will have the feel of a gritty crime drama rather than a conventional comic book movie. It will be set in the 1980s and chart The Joker's rise through the criminal underworld of Gotham City.

Todd Phillips, known for The Hangover trilogy and War Dogs, is set to direct and co-write with Scott Silver.

Phoenix was considered for the role of Lex Luthor in Warner Bros' Batman v Superman: Dawn of Justice, and was in talks to star in Marvel's Doctor Strange. Nothing came of those talks and the respective roles went to Jesse Eisenberg and Benedict Cumberbatch.

Phoenix made his name in films such as Gladiator, The Master and Her. He has most recently starred in Lynne Ramsay's You Were Never Really Here, Gus Van Sant's Don't Worry, He Won't Get Far On Foot and Garth Davis's Mary Magdalene.