Turtle Moon transports the listener to Verity, Florida, a place where anything can happen during the month of May, when migrating sea turtles come to town, mistaking the glow of the streetlights for the moon.
A young single mother is murdered in her apartment and her baby is gone. Keith, a 12-year-old boy in the same apartment building—the self-styled "meanest boy" in town—also disappears. In pursuit of the baby, the boy and the killer, are Keith's divorced mother and a cop who himself was once considered the meanest boy in town. Their search leads them down the humid byways of a Florida populated almost exclusively by people from somewhere else; emotional refugees seeking sanctuary along the swampy coast.