U.S. Marshal Nevada Jack McKenzie halts a runaway stage and finds the driver dead and his helper badly wounded, and the stage robbed of a gold shipment. John Corbett, owner of the saloon and secret leader of the outlaw gang, tries to induce the mine owners to help him get the express company franchise, insisting that he can stop the holdups. To mislead them, he pretends sympathy for Jane Burns, current holder of the franchise. Nevada's pal and fellow Marshal, Sandy Hopkins, arrives in town incognito, shows antagonism toward Nevada, wins Corbett's support and is made sheriff. Ned Turner, Jane's sweetheart and stage guard, urges her to keep the franchise and, when Nevada offers to drive the stage, they win permission from the mine owners to try one more trip over the unused Lost Trail.