Few actor-director pairings are more celebrated than the collaborations between Leonardo DiCaprio and Martin Scorsese. The duo is next set to team up with Scorsese's other muse, Robert De Niro, to make the Western drama Killers of the Flower Moon, based on the novel of the same name by American journalist David Grann. The film's screenwriter Eric Roth told Collider that the ambitious, $200 million budget movie is going to be one of a kind.

"I know Marty's trying to make a movie that's probably the last Western that would be made like this, and yet, with this incredible social document underneath it, and the violence and the environment. I think it'll be like nothing we've ever seen, in a way. And so this one is, to me, one for the ages."
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The book Killers of the Flower Moon investigates a series of murders of wealthy Osage people that took place in Osage County, Oklahoma in the early 1920s. The land had yielded evidence of huge oil deposits, which belonged to the Osage people. A grim plot was hatched to eliminate the owners of Osage County so the administrators of the land could lay claim to the oil deposits instead.

The incident remained shrouded in mystery for some time, with the total number of Osage people who were murdered estimated to be much higher than the official count. The newly formed FBI was called in to investigate the murders, which eventually led to the trial and conviction of cattleman William Hale as the originator of the entire plot.

According to Roth, while the description of the story does not make it sound like a proper western, its primary ethos belongs to the western genre.

"I mean, people will be in suits and things because it's 1921. It's during the prohibition, but the ethos I think is very Western. And also, I think Western justice, about how they said that you couldn't find 12 white men to convict a white man of killing a native American. You'd have a better chance of having them convicted of kicking a dog. And that's kind of the feeling on that. And then also, you have these incredible people, the Osage family that a character comes and marries into, and who's a villain and who isn't. And then into that comes a kind of heroic guy - Tom White, his name was, who Jesse Plemons is playing - who was in the Texas Rangers, and you couldn't get more Western than that."

While fans naturally assumed that DiCaprio would be playing the lead role in the Martin Scorsese film, there were rumors that Jesse Plemons had been cast in the lead instead, while DiCaprio would have a supporting role. Roth explained that both Plemons and DiCaprio have equally meaty roles in the script, adding that, "Leo's part is very complicated and very interesting. It's a smart part for a smart actor to play. I mean, if Montgomery Clift was alive, I think he might think of playing him." This news originated at Collider.