In the 1920s, approximately two-dozen members of the oil-rich Oklahoma tribe known as the Osage Nation were killed in what the Oklahoma Historical Society recorded as “violent or suspicious deaths.” Almost a century later, David Grann authored a nonfiction book on the crimes called “Killers of the Flower Moon: The Osage Murders and the Birth of the FBI.” “In desperation, the young [FBI] director, J. Edgar Hoover, turned to a former Texas Ranger named Tom White to unravel the mystery,” the book’s summary notes. “Together with the Osage they began to expose one of the most chilling conspiracies in American history.” The crimes were scrutinized by the U.S. Bureau of Investigation — a precursor to the FBI — in what would become known to the Osage as a “Reign of Terror.” Now, that century old mystery has been picked up by legendary filmmaker Martin Scorsese and turned into what is expected to be a surefire Oscar contender — one that could perhaps earn the director his second Academy Award for Best Director. Seldom has a trailer looked so ominous, a tone undercut by repeated references to wolves hiding in plain sight. Leonardo DiCaprio, Robert De Niro and Lily Gladstone star as the film’s leads, while Brendan Fraser, Jesse Plemons and John Lithgow, among others, round out a star-studded cast. “Killers of the Flower Moon,” produced by Apple Studios, debuted at Cannes this weekend and was received with a nine-minute standing ovation once the credits rolled. It is slated for a theatrical release on October 6.