Very well done, lot of research, interviews, etc obviously went into this book. It's now getting a lot of attention since HollyWEIRD found out about it and are making a movie. I don't have much faith they'll do a good job.
This atrocity should be taught in EVERY school in Oklahoma but I don't have much faith it ever will be, like a lot of things which don't paint our country, state, etc in a good light. So it's up to us to discover some history and/or another version of history different from propaganda pieces we've been taught. This is one of those books every American should read or at least hear a summary of, so that history doesn't get repeated as that old adage says.
There are a LOT of skeletons in the closet, a lot of crimes committed, many of which the FBI elected not to pursue. Find a fall guy, in this case, William Hale, who no doubt was responsible for many of the murders, but he was hardly the only one. Yet J. Edgar Hoover, what a piece of work he was, elected not to have his Bureau investigate any further once Hale was successfully prosecuted as author David Grann points out later in the book. Kudos for Grann for doing further research on this...after speaking to some of the Osage members whose family members were murdered. RIP to those who perished, and sincere condolences to all who lost loved ones!