So it's kind of about the birth of the FBI, but that's not really the interesting part of this. This is the true story of how members of the Osage tribe were assassinated in the 1920s (and beyond) for their wealth, which they got from oil. Grann brilliantly and skillfully paints a picture of the depth and breadth of corruption on every level as white people conspired to rob, cheat and kill the Osage people for the enormous wealth, which they got because the desolate land that the government resettled them on happened to have huge reserves of oil beneath it. David Grann sets the story in its proper historical, political and social context to show the impact of the Osage murders on the Osage people, as well as the other ways that they were disenfranchised on their own land by the US government and by white people who settled in their community. This was breathtaking and a real page-turner...it reads like a western rather than nonfiction, even though it is highly detailed.