In 1975, a man stumbled upon a box of hand-sewn notebooks in a house set for demolition in Wadesboro, North Carolina. After thumbing through the delicate pages and finding them written in code, he passed the books to a retired NSA cryptanalyst who deciphered them, uncovering the recorded life of a white Southern farmer named William Thomas Prestwood. The diaries offered a ground-level view of a 19th-century man who passed his days recording eclipses and dissecting rabbits and calculating planetary orbits and reading Goethe and sneaking into barn lofts and closets with dozens of lovers. “The reader is left,” the codebreaker wrote, “with the lasting impression that here in these pathetic little books is the very essence of Everyman’s life from the cradle to the grave.” But to author Jeremy Jones, this strange farmer was no Everyman. He was his great-great-great-great grandfather.

Cipher reanimates Prestwood, warts and all, following the author’s ancestor as he courts women and hides runaway slaves, as he fathers children with his wife and with an enslaved woman, as he mines for gold and befriends Daniel Boone’s great nephew, and as he rubs shoulders with a young Zebulon Vance and raises sons soon to die on the fields of Gettysburg. With research, Jones fills in the blank spaces of this Everyman’s life. Along the way, Jones begins tracking his own life alongside the fascinating arc of this long-ago forefather, forging an intimate relationship with a man whose own account, in Jones’s expert hand, begins to take on texture, drama, emotional resonance—even as the author uncovers curious and disturbing details about his ancestor. And thus, about his family. About himself.