In the aftermath of the Civil War, a group of young Confederate veterans led by Jesse James and his brother Frank return to their devastated Missouri homes, only to find them ravaged by the war and their families dispossessed by ruthless railroad companies. As the encroaching railroads begin forcibly buying up land for pennies on the dollar, a sense of injustice ignites within the brothers. Frustrated and angered by the corrupt practices of the railroad magnates and their hired gunmen, Jesse, Frank, and their friends decide to take matters into their own hands. They begin a daring crusade against the railroads, initially aiming to reclaim what was unjustly taken from their families.

Their actions quickly escalate from local vigilantism to notorious bank and train robberies, drawing the attention of the law and turning the group into celebrated folk heroes among the oppressed settlers. Despite their intentions, their journey into outlawry sets them on a collision course with the authorities, and a determined detective is tasked with bringing them to justice. As their exploits grow bolder, the group, now dubbed the James-Younger Gang, finds itself increasingly hemmed in by lawmen and bounty hunters alike. The camaraderie among the bandits is tested as they navigate their newfound infamy and the harsh realities of their chosen path, leading them to confront the consequences of their actions.