It is possible to read David Grann and Kathryn Red Corn as foils. Their relationship as foils is clearest in Chapter 22, when Red Corn shows Grann the missing panel of a photo depicting Hale among the Osage:
The Osage had removed his image, not to forget the murders, as most Americans had, but because they cannot forget.
Grann and Red Corn are both historians, in their own ways. Grann catalogs history through journalism, and Red Corn catalogs the same history in a museum. Grann is not most Americans, seeking to forget Hale and the murders. He is sensitive throughout his investigation to the long-lasting trauma the Osage are still contending with years and years after the murders. He seems truly to want to help them by telling the story of what happened to their community. However, this scene juxtaposes his and Red Corn's respective relationships to the history they both aim to preserve. For Red Corn, who is Osage herself and lives and works in the place where the murders happened, keeping history is as painful as it is important. She is one of the people who cannot forget Hale's face in the picture.
By contrast, this scene makes it clear that Grann is driven by curiosity. He wants to get to the bottom of the case, to prove himself as a detective, and to see the harrowing image of Hale sitting among the people whose murders he would go on to orchestrate. Even if there is nothing inherently sinister about Grann's motives, he will never have the same relationship to the case as Red Corn. He will always be more like Tom White, an outside investigator who can't quite get to the bottom of what happened. Like White, Grann's efforts to uncover more of the truth will ultimately leave him less satisfied than he would wish because no detective work can ever ease the lingering pain of the violence the Osage faced during the Reign of Terror.