Other alternative protagonists keep drifting into view. The film is adapted from David Grann’s book, which is subtitled “The Osage Murders and the Birth of the FBI”, and yet the main agent responsible for cracking the case, played by Jesse Plemons, isn’t introduced for two hours. Incidentally, the lawyers in the subsequent court case, played by John Lithgow and Brendan Fraser, don’t turn up for another half-hour after that. Or what about Mollie, who trusts Ernest, but is also a proud, cool-headed, perceptive woman who is determined that justice be served? Might the film have had more purpose if it had concentrated on her? There are fascinating revelations about how the Osage people are infantilised, and how they conduct their business, but these should have accounted for a bigger chunk of the three-and-a-half hour running time.
The last half-hour in particular prompts mixed feelings because, despite some touching, sober scenes, it becomes a Coen Brothersesque farce about just how stupid criminals can be. It’s the most enjoyable part of the film, but also the most questionable. If Scorsese was set on making a blackly comic romp featuring a patronising gangster and his numbskulled nephew, maybe he shouldn’t have used the real massacre of Native Americans as its subject.
★★★☆☆
Killers of the Flower Moon is on general release from 20 October.
Love film and TV? Join BBC Culture Film and TV Club on Facebook, a community for cinephiles all over the world.
If you would like to comment on this story or anything else you have seen on BBC Culture, head over to our Facebook page or message us on Twitter.
And if you liked this story, sign up for the weekly bbc.com features newsletter, called The Essential List. A handpicked selection of stories from BBC Future, Culture, Worklife and Travel, delivered to your inbox every Friday.