There are many chapters in U.S. history that we’d probably rather forget. Some, we’ve successfully managed to forget altogether. The new film Killers of the Flower Moon covers such a chapter, making that last point painfully clear in its final act.

The film comes from director Martin Scorsese, who worked on the screenplay with Eric Roth. It’s based on true events, captured in a book of the same name from David Grann. It’s set in Oklahoma in the 1920s, just after World War I. It’s set in Osage territory as its people are both reaping the rewards and suffering the dangers of discovering oil.

The discovery of oil on the land has made the Osage wealthy beyond measure. It’s brought them opportunities, comfort and those that would attempt to take what they have. This, in turn, has led to a series of murders.

Early in the film we get reference to those murders as we meet Molly (Lily Gladstone), whose mother and sisters have benefitted from the discovery. But they see the danger as well. In addition, the family is suffering. Molly herself suffers from diabetes owing in part to the newly rich diet she’s enjoying.

In the meantime, Ernest (Leonardo DiCaprio) is returned from the war and looking to make his fortune. He turns to his uncle, King Hale (Robert De Niro), who lives as a friend to the Osage in the middle of their land. He, however, makes his fortune by preying upon the people in the land.

When Ernest falls in love and marries Molly, King Hale sees an opportunity. It continues a series of events that threatens to cripple both families.

The book is an exploration of the turbulent times. As the film makes reference, Oklahoma in the 1920s wasn’t a friendly place to those who weren’t white. The laws, too, weren’t favorable to oppressed minorities seeking justice. It took a lot to even get someone to look into these killings.

The other half of the book is about the formation of the FBI, which was a part of this investigation. That isn’t touched on widely in the film as we get more of a focus on these people and the damage done to the Osage nation. It’s a long and often difficult story but the craft here is strong.

Scorsese, who appears in a minor role near the close of the film, clearly cares about this story and about being faithful and doing justice to the Osage who suffered. It’s a well-crafted film that is compelling and features some beautiful cinematography.

The performances are quite strong, too. De Niro does good work, as does Jesse Plemons in a supporting role later in the film. But this comes down to DiCaprio and Gladstone, both of whom are fantastic. Their final scene together is tense, emotional and heart-breaking, as befits the story.

This film will rightly be a contender as we come to awards season. It’s a difficult watch and a difficult story but an important story to tell.

Killers of the Flower Moon is now playing in theaters nationwide.

Matthew Fox is a graduate of the Radio, Television and Film program at Biola University, and a giant nerd. He spends his free time watching movies, TV, and obsessing about football. He is a member of the FSWA. You can find him @knighthawk7734 on Twitter and as co-host of the Fantasy Football Roundtable Podcast.