Updated

It was July of 1946 when two young black couples riding along a rural road were stopped by a white mob in Georgia — at Moore's Ford Bridge overlooking the Apalachee River. The mob dragged the victims from the vehicle, led them to the riverbank and shot them multiple times.

The brazen lynching horrified the country that year. But a federal grand jury indicted no one, and investigators over the decades since also failed to crack the case. Last month, Georgia's top law enforcement agency closed its latest investigation, just months after the FBI concluded its latest review, saying all the likely killers were dead.

Despite all that, activists and others who've spent countless hours studying the killings and raising awareness hope answers will still surface.