Looking for Answers about David C. Cook Sinner: A Novel?

A brutal attack at St. Anthony's Cathedral leaves behind a symbol of the mythological Sinner--a phenomenon that's been kept alive in conspiracy circles and urban legend since before the Civil War. The symbol--and the legend attached to it--spark the curiosity of investigative crime writer and amateur detective CK Ivors. But CK and her team soon discover that they aren't the only ones on the case when she meets the strange and mysterious Loftis Johnson, who's also tracking The Sinner for reasons of his own. Are they on a collision course where they'll never be the same?