Desert Storm hero Sam Harper is killed during a friendly fire incident in Kuwait. His body is sent back to his small hometown, where it is to be buried on the Fourth of July. However, his death does not prove to be final, as Harper's love for his country and his disdain for those disrespecting it transcend the grave. The festering anger about his own demise and a fervent nationalism fuel his return from the dead. The townspeople remain unaware that they now host a vengeful, undead soldier in their midst. Harper, shrouded in patriotic zeal, dons his old military uniform and takes on the persona of Uncle Sam, a macabre twist on the iconic figure of American liberty.

As the town's Independence Day celebrations commence, Sam embarks on a bloody quest to punish those he deems unpatriotic or lacking in American values. A group of teenagers, busy with the youthful indiscretions of vandalism and drug use, become the initial targets of his ruthless rampage. Amidst this chaos, Sam's young nephew, Jody, is both awestruck and inspired by his uncle's military past, and he idolizes him. Jody's fascination leads him to explore his uncle’s belongings, planting the seeds of an influence that threatens to shape the boy's impressionable mind, reflecting the complex interplay between heroism and the hazards of blind patriotism.