Snake Ripley wants nothing more than to escape from Rockton, Mississippi, where he lives with his father and brother. Snake runs the family garage, an unprofitable business in the dying town. His father is all but dead, gradually wasting away as he sits in front of the television set drinking beer, watching wrestling, and reading thirty-year-old copies of TV GUIDE. Snake’s brother, Leslie, is not dead but “damaged,” having suffered brain trauma at birth.
Truly Crawford, the daughter of a wealthy racist and a would-be artist, is not sure what she wants, but it is not in Rockton. She goads Snake into taking dramatic action to improve his life, not necessarily to help him, but just for some excitement. Crawford is a thrill seeker, and her Jaguar and minor escapades are no longer enough to satisfy her.
Snake and Truly are not the only ones with plans. Leslie’s mind is deteriorating even further; having become obsessed with religion, he announces repeatedly that he is going to “save” the Ripley family. Their father, who early in the book contemplates suicide, becomes convinced that he has a mission to perform before he dies. He kills several of Rockton’s citizens, but there already have been two recent murders in Rockton. The search for the killers draws in Junior Crawford, Truly’s father, who decides that he will be the hero that finds and kills the murderer. The climax of the book is typically violent Southern Gothic, featuring a chase into the Black Swamp. Indeed, FINAL HEAT is Gothic throughout, with dramatic, tormented characters grasping wildly for what they think they want, but what will in fact destroy them.