KILLERS of the FLOWER MOON-Flows Slow with Leo and DeNiro

KILLERS of the FLOWER MOON ("KFM") is a cinematic feature broadly based on David Grann's historic book.  KFM conveys the heinous murders of scores of people of the Osage nation. These rampant killings went uncontested by law enforcement in the 1920s. A shameful note: the OK massacre of the African Amer. population and businesses also took place in 1921.  A scene in K FM is in theater and a newsreel is depicting the Tulsa Race Massacre.  Both melees in OK have mostly gone unheralded as the mass murders were committed by resentful, white people with the intent to raze both races and confiscate their lands and fortunes. The film also shows the Klan marching proudly and unobstructed down the town's main streets. Dir. Scorsese is to be commended for the historic significance he's canonizing on film. The conveyance of under represented blights on humanity must not be ignored.  There's much to admire in this epic feature, beautifully filmed and acted.  Scorscese tapped into his reliable/bankable A listers.  The  brilliant ensemble cast include DiCaprio as Ernest Burkhart, Robert DeNiro as (Ernest's uncle, William Hale), Jessie Plemmons (FBI investigator, Tom White) and a bravado performance by Lily Gladstone (Ernest's wife Mollie Burkhart of the Osage nation).  The film is a demanding 4 hour saga difficult to sit through in its entirety. The events and people are factual but this murderous/crime thriller fails to rouse above a tepid tempo of intrigue.  The duplicitous killers are known to the viewer. Nevertheless, the plot needlessly  meanders at a plodding pace lacking suspense.  The impact of the premeditated intermarrying in order to siege Osage's oil land rights and then assassinating spouses and family members didn't register strong enough shock or repugnance. Ernest courts and marries Mollie as instructed by his svengali uncle, William and then slowly tries poisoning her while coddling her as she writhes in pain. These scenes were agonizing to watch. However, DiCaprio with a Gomer Pyle pout and blank expression was pitifully malleable without seeming credible.  DeNiro's narcissism and justifications for destroying the Osage to enrich himself fared better in his cringeworthy role. Plemmons, as an FBI investigator Tom White was summoned to OK after Mollie ventured to D.C., met with the Pres. Harding to plead for protection for her people being slain.  Plemmons was intriguing in his portrayal as an unassuming and stalwart investigator.  Ultimately, Scorsese's fact based storytelling unveiled a domestic intimacy that didn't feel  immediate or despondent enough to evoke terror or pathos. Ernest gushed, "I love money, I surely do," at the poker table but don't bet on him convincing a sagacious Mollie he's a devoted, selfless husband. FKM does justice to events long brushed aside.  Yet, it doesn't fully broker the horror or abhorrence committed against the Osage nation.