Rage at Dawn chronicles the notorious Reno posse, a band of criminal brothers in 1866 Indiana. James Barlow (Randolph Scott, Ride the High Country) is an undercover detective assigned to bring the Reno brothers to justice. Barlow infiltrates the gang as one of their own, and once inside, he learns that the gang has been bribing officials to overlook their crimes. Unable to trust any local leaders, Barlow devises a plan to set up the Renos at a pre-dawn train heist. But before his work is through, he must contend with an angry lynch-mob that has stopped him in his tracks.