The Hundredth Man: Carson Ryder/Harry Nautilus #1 (Unabridged‪)‬

When bizarre and cryptic messages are found on a pair of corpses in Mobile, Alabama, junior police detective Carson Ryder and veteran cop Harry Nautilus find themselves in a mysterious public-relations quagmire pitting public safety against office politics. With the body count growing, Ryder must confront his family's terrifying past by seeking advice from his brother, a violent psychopath convicted of similarly heinous crimes. Ryder finds himself falling for Ava, the striking pathologist processing the gruesome corpses. But Ava's past holds its own nightmarish secrets.
Ryder and Nautilus come to realize someone close to them is the killer's ultimate target - and time is running out before the killer plans to strike again.