Martin Scorsese's upcoming film "Killers of the Flower Moon" brings to light the dark history of the 1920s Osage murders in Oklahoma. Based on David Grann's book, the movie tells the story of the systematic killings of wealthy Osage Native Americans for their oil money. The film highlights the cultural prejudice and white supremacy that allowed these crimes to occur, as well as the erasure of this chapter in American history.