Chinonye Chukwu’s new film reminds us that before his gruesome murder galvanized a civil rights movement, Emmett Till was a 14-year-old boy with a doting mother.Some stories can seem too difficult to tell, though that doesn’t seem to have crossed the mind of the director Chinonye Chukwu. In “Till,” her haunted and haunting movie about Emmett Till, the 14-year-old whose barbaric murder in Mississippi in 1955 by white supremacists helped galvanize the civil rights movement, Chukwu revisits the past while doing something extremely difficult. She makes this grim American history insistently of the moment — and she does so by stripping the story down to its raw, harrowing emotional core.In brisk strokes both sweeping and detailed, Chukwu — who shares the script credit with Michael Reilly and Keith Beauchamp — revisits Till’s life, winding back the clock to Chicago in 1955. There, the cherubic-faced Emmett (a tender Jalyn Hall) lives with his widowed mother, Mamie (a superb Danielle Deadwyler), in a cozy house and is eagerly preparing to visit relatives in Mississippi, a trip that hangs over his mother like a worrying cloud. Yet Mamie dotes on Emmett (she calls him Bo) and, as a gift, buys him a wallet at a department store, where she tartly rebuffs a white salesclerk who tries to steer her toward the basement.By the time that Emmett is riding a train to the South — midway through the trip, the Black passengers stand and move en masse to the rear — a divided world of post-World War II optimism and jarring racial segregation has opened up. These divisions widen once Emmett arrives in Mississippi, where he stays with the family of Mamie’s uncle, a sharecropper, Moses (John Douglas Thompson). Soon, Emmett is helping Moses and his children pick cotton under the relentless sun — the palette suggestively lightened — and the camera sweeps over Black bodies toiling in the field as Antebellum America comes to unsettling life.The horrors of that world soon emerge with devastating consequences. Emmett, along with some relations, visits a small grocery store that caters to Black customers but is run by white people. Things rapidly spiral downward when Emmett walks into the store and meets the contemptuous gaze of the woman behind the corner. The Northern salesclerk who insulted Mamie earlier was just a better-mannered racist; he was also an ugly foreshadowing. Now, away from Mamie and the life he knows, Emmett amiably tries to engage the woman, Carolyn Bryant (Haley Bennett), whose hostility ends in catastrophic violence. That evening, several white men kidnap, torture and murder Emmett, throwing his mangled body in a river.Chukwu doesn’t show Till’s torture and death, a decision that is a clear, emphatically ethical artistic choice. “Till” is the third feature-length movie that she has directed, the latest following her 2019 drama “Clemency,” about a Black prison warden in crisis, and her work here is impressive. She handles the larger-scale period backdrop of “Till” and sprawling cast with confidence, using her expanded tool kit prudently and without sacrificing the intimacy that helped distinguished “Clemency.” And, just as she did in that drama, which was at once anchored and elevated by Alfre Woodard’s powerful lead turn, Chukwu distills a story — its gravitational force and emotional depths — into the movie’s central performance.With fixed intensity and supple quicksilver emotional changes, Deadwyler rises to the occasion as Mamie, delivering a quiet, centralizing performance that works contrapuntally with the story’s heaviness, its profundity and violence. The weight of Emmett Till’s murder, the horror of it — as well as both the history that preceded his death and that which followed it — is monumental, impossible, really, for one movie. Rather than attempt to convey that significance in its full sweep, Chukwu condenses it into meaningful details, fugitive moments, tranquil ellipses, explosive gestures and, especially, the face of one woman in joy and in agony.Chukwu keeps focused on Mamie even as the world presses in, including after Emmett’s death when she’s swept up in a larger national drama and arranges an open-casket funeral — a bold, far-reaching decision — and then later travels from Chicago to Mississippi to attend the trial of his murderers. During the trial, a grotesque sham, reporters swarm, flashbulbs pop and highlighted figures enter and exit, including Medgar and Myrlie Evers (Tosin Cole and Jayme Lawson). The movie doesn’t go deep into the era’s policies and politics, but while the trial unfolds it sometimes slips into explanatory, near-pedagogical mode, including in some scenes that seem more for the viewer’s (perhaps white viewer’s) benefit than for the actual story.In the decades since he died, Till’s murder and the still-shocking photographs of his body have been the subject of innumerable news stories, scholarly articles, nonfiction books, novels, poems, documentaries, podcasts, websites and exhibitions. At the 2017 Whitney Biennial, a painting of his corpse by the white artist Dana Schutz drew protests and criticism from Black artists. Historical markers installed in Mississippi that designate significant locations in his murder have been repeatedly vandalized. And, in March, Congress finally approved a bill — known as “the Emmett Till Antilynching Act’’ — making lynching a federal hate crime. Nearly 70 years after his death, his legacy and body remain contested ground.Perhaps that’s why I keep returning to the image of Mamie with her mother, Alma (Whoopi Goldberg), who’s sitting near-immobilized with grief after his death. Alma’s limbs hang heavily, as if they had turned to lead, an image that mirrors Jesus as the Man of Sorrows and summons up visions of other grieving Black families. Here, as elsewhere, including the scene of Mamie with Emmett’s corpse that evokes innumerable pietàs, the sanctity of these bodies is as undeniable as their humanity. In the end, what makes “Till” cut deeply is Chukwu’s insistence that before Emmett was a victim of pathological racism and an emblem for change, he was a boy, a friend, a cousin, a grandson and Mamie’s son — a beautiful, loving and loved child.TillRated PG-13 for racist violence and language. Running time: 2 hours 10 minutes. In theaters. More