The setting is Atoka County, Alabama -- the time is somewhere after the peak of the civil rights movement, after cities such as Birmingham, Alabama were out of the headlines. The movement is coming to the sticks, including Atoka County, and a lot of the white residents don't like it and are prepared to commit felonious assault, rape, or murder to get their point across. In the middle of this powder keg are two men on either side of a very dangerous line -- County Sheriff "Big Track" Bascomb (Lee Marvin) and Mayor Hardy (David Huddleston). Each man is playing both ends against the middle in the impending race war -- Bascomb wants to keep the peace as best he can, blocking the local klavern of the Ku Klux Klan from their worst excesses and making sure that the Klan's business and the county's business remain separate; Hardy, who also owns the lumber company that employs most of the county and the bank on which most of the residents depend, wants a good environment for business, which includes keeping enough poor blacks around to do the most menial work for the miserable pay he's willing to fork over; this, in turn, requires that they be too scared to ask for too much, including better treatment, but not so scared that they leave the county altogether, which would wipe out his business. Between them is Breck Stancill (Richard Burton), an eighth-generation resident with lots of land but little money and even fewer friends; a wounded war veteran and loner, he still resents the lynching of his grandfather and no longer respects what the white south purports to stand for -- he's even allowed dispossessed blacks to live for free on his property, angering the poor whites around him even more. Bascomb would like Stancill to be a little less high profile, while Hardy would like him to sell out and disappear, and wouldn't mind it if the local Klan helped that process along by trying to kill him. Bascomb's balancing act fails because of two events -- Nancy Poteet (Linda Evans) is raped one night, apparently by a black man, which precipitates the murder of a black teenager and her being violently ostracized by the white community; and a civil rights rally is planned for the town, bringing in lots of "outside agitators" and getting the local klavern eager to act against them. The prime mover in all of this is Big Track's deputy, Butt Cut Bates (Cameron Mitchell), a hardcore klansman who won't be reined in by Hardy and who is not above raping a black woman prisoner (Lola Falana) that he's arrested illegally, or trying to kill Stancill; directly opposed to him is Garth (O.J. Simpson), a young black man who witnessed a Klan murder and, in response, gets a rifle and starts meting out justice on his own. Before it's over, a major part of the county is at war and the bodies are falling everywhere.