The film uses 27 years' worth of research by Keith Beauchamp, whose efforts led to the reopening of Emmett Till's case by the United States Department of Justice in 2004.
Simeon Wright, Emmett Till's cousin and an eyewitness of the event, served as a consultant to the project until his death on September 4, 2017.
In an interview on "Fresh Air" on NPR on November 1, 2022, director Chinonye Chukwu indicated that she didn't let Danielle Deadwyler (playing Emmett Till's mother, Mamie) and Sean Patrick Thomas (portraying Gene Mobley) and a few other characters actually see the made-up body that portrayed Emmett's mutilated corpse until they started shooting the scene.
It is noted several times that Emmett's father died overseas in military service. In fact, he was executed in 1945 after being court-martialed for killing one and raping two other Italian women. He and Mamie had divorced in 1942, and a court obliged him to enlist after violating a restraining order. The Army only told Mamie he had been executed for "willful disobedience", and the full truth wasn't revealed until 1955.
Disfigured in death, Emmett Till's swollen, virtually unrecognizable face was made famous in a photograph by David Jackson, first published in Jet magazine, showing the boy's mother Mamie Till Mobley looking down on her son.