Private investigator Geronimo "Fitz" Fitzgerald plies his trade in the coastal Florida city of San Marco. No case is beneath his dignity: taking photos of cheating spouses or digging up dirt on local big shots or serving legal papers to the city's miscreants. They all pay the rent and keep the rum flowing to drown out the voices from his past.

However, Fitz is reluctant to take a job helping high school football coach Mack Thorpe, mainly because of the coach's uncontrollable temper. But the case, in which Thorpe is the main suspect in the rage-fueled murder of a US senator, is too intriguing to turn down. When Fitz teams up with local journalist Mattie Castro, they learn that the senator's death, as well as subsequent murders, are tied to the senator's groundbreaking policy to alleviate homelessness in his district.

The investigation leads Fitz and Mattie from the cream of local society to the clutches of a swamp-dwelling, meth-cooking family. Things turn from grim to worse when Mattie is lured away by the killer, who is intent on making her another victim, even if it means killing Fitz first.