Upstate policeman Jeff Wilson is sent undercover to a small southern town to bust a discreet moonshine operation that quietly fuels the local economy. He is warned by the police chief about past investigations that failed due to uncooperative locals and the county’s proud Sheriff Bull Tatum Charles Elledge, who resists outside help and remains suspicious of any intrusion.
Behind the scenes, the Barefoot bootlegging business is quietly run by the widow Stella Holcomb Tonia Bryan and her three daughters, Rosa Lee, Vicky, and Mary Ann Sherry Robinson, who live just outside Tatum’s jurisdiction in Red Rock County. Mary Ann, dressed as a man, secretly delivers moonshine to Otis Perkins, a local gas station and diner owner. In response to the crackdown, Sheriff Tatum and his deputy Clyde set up roadblocks to search incoming cars, but Mary Ann easily evades them.
Upon arriving in town, Wilson is run off the road by Perkins’s troublesome sons, Culley Joe Jeff MacKay, Clarence Mike Muscat, and Junior. He is found unconscious by the Holcombs, who immediately take him in for recovery. A country-savvy Wilson remains undercover, telling the Holcombs that he is simply in search of work. As he continues to stay with the family and begins work at Perkins’s gas station, he and Mary Ann develop feelings for each other; Culley Joe grows jealous and clashes with Wilson. Sheriff Tatum also grows suspicious of his presence.
As Wilson begins to uncover the Holcombs’ and Perkins’s operation, the Perkins’s tomcat sons ambush the unattended Holcomb girls at a swimming hole. When Culley Joe forces himself onto Mary Ann, Wilson intervenes and fights the boys off, promising to protect her. He later gives Mary Ann his mother’s pin to quell her doubts about his genuine intentions. Mary Ann privately begins to regret the family’s illegal business, as Wilson becomes torn between his professed feelings for Mary Ann and what he discovers about the Holcombs.
One night, Tatum discovers his daughter Nadine’s sexual affair with Culley Joe and angrily arranges a shotgun wedding. At the afterparty, Wilson leaves to investigate the Holcombs’ moonshine distillery, but Tatum follows. Upon confrontation, Wilson reveals his undercover status and presents his police credentials, which Tatum accepts and inquires about the moonshiners’ identities. Wilson, however, lies to cover for the Holcombs, telling Tatum that they have already been arrested. They then destroy the distillery.
When they return to the party, Tatum publicly announces the discovery of the moonshining operation and reveals the truth about Wilson, angering Mrs. Holcomb and breaking Mary Ann’s heart. Disgraced, Wilson returns home and decides not to reveal his findings to the police chief. He reconciles with the Holcombs and Perkins, telling them that he has resigned his special agent position. Wilson then returns to Red Rock County to reunite with Mary Ann, and secretly helps the family rebuild their distillery.
