Mamie Till became an educator and activist in the Civil Rights Movement after the death of her 14-year-old son, Emmett, who, in 1955, was beaten severely, shot dead then thrown into the Talahachee river with a 75lb cotton gin fan tied around his neck with barbedwire by white supremacists for whistling at a white woman, while visiting his cousins in Money, Mississippi. Mamie Till insisted that the casket containing her son's body be left open to show the world what they had done to him. The film is told entirely from her perspective. Emmett Till's murder is heard, but not shown in the film.