The summer of 2020. COVID-19 is spreading like wildfire. Racial reckoning and Confederate monuments fuel nationwide protests. And Asheville, North Carolina, is not immune.

When Sam Blackman and Nakayla Robertson see an elderly man knocked to the pavement by a Confederate sympathizer, they rush to his aid. The assailant runs away and the fatally injured man struggles to say, "I'm so sorry, Nakayla. Can you forgive me?" Nakayla has never seen him before. Why does he want her forgiveness?

Nakayla learns the man, Henry Nelson, was a retired homicide detective who had investigated her father's death fifteen years earlier. He'd closed the case as a suicide. But when Nelson's widow brings Nakayla the case files her husband stole from police records, she and Sam realize the old man had been reviewing the investigation, evidently questioning his earlier conclusions.

But then the detective's widow is murdered and Sam and Nakayla find themselves confronting a killer who will stop at nothing to keep a crime from the past buried in the past. Their only clue, a declassified FBI file that J. Edgar Hoover kept on Martin Luther King, Jr. A file that detailed threats against the civil rights leader during his trips to Asheville. A file found on the desk of Nakayla's father the night he died. A file that holds the key to the secret. The Secret of FBI File 100-3-116.