In the closing days of the Civil War, Confederate Captain Jim Farraday (Van Johnson) steals a shipment of Gatling guns from the Northern army, and by pretending to be the proprietor of a traveling medicine show, manages to smuggle the guns back through enemy lines. However, when disloyal Rebel Brett Manning (Richard Boone) steals the guns from him with a plan to sell them to the Indians, Farraday surrenders to the Union in order to enlist their help getting the weapons back. Once Manning has been killed and the guns retrieved, it's time for Farraday to be put on trial - but nurse Nora Curtis (Joanne Dru), who has fallen in love with him, pleads eloquently for clemency. Farraday is ultimately allowed to escape, but only after promising that he will marry Nora when the war ends.