In Prohibition-era Kentucky, Internal Revenue agent Frank Long figures he could make a dishonest buck by squeezing the moonshine producers. First, he targets an old army buddy, John Martin aka Son, and demands a cut of the moonshine profits in exchange for looking the other way. However, with Prohibition rumored to soon come to an end, Son figures he could refuse Frank's offer and wait until after the federal elections that promise to legalize alcohol production. Annoyed by Son's refusal, Frank lodges himself in a local hotel and starts a daily harassment routine against Son and other local moonshiners. Faced with an armed response from the outraged moonshiners, Frank realizes he is outgunned and outnumbered. He decides to call-in hired help, Dr. Emmett Taulbee and his gunman Dual Metters, two unscrupulous gangsters from the big city. However, Frank and the two gangsters fail to intimidate Son and the other moonshiners. The local town lawman, Sheriff Baylor, is friendly to the moonshiners and frequently 'samples' their product. Fed-up with the situation, Dr. Emmett Taulbee appeals to his gangster friends from the East who arrive armed-to-the-teeth in town. As a federal agent, Frank cannot condone any killing and he asks Taulbee and his gangster friends to refrain from killing anyone. The only shooting allowed is that of the moonshine stills. Nevertheless, things get out of hand when the gangsters kill the sheriff and his deputy. When Frank protests the killings, Taulbee tells him to get lost. Now unwilling to share any profits with Frank, Taulbee chases Frank out of town and aims to confiscate all the moonshine for himself and his gangsters. He targets Son's farm first because it hides the largest stash of moonshine casks, worth tens of thousands of dollars. Expecting this, Son fortifies his farm with barbed-wire, sand-bags, booby-traps and firing positions. When Taulbee and his men converge on Son's farm, Son and his employee Aaron try to defend it. Having second thoughts about leaving town and full of remorse, Frank decides to join Son and help him fight off Taulbee's gang.