In Old Monterey

In Old Monterey is a 1939 American Western film directed by Joseph Kane and starring Gene Autry, Smiley Burnette, and June Storey. Based on a story by Gerald Geraghty and George Sherman, the film is about an army sergeant and former rancher who runs into opposition from local ranchers when the United States Army sends him to purchase their ranch land needed for a strategic air base.

After some investigation, Gene suspects that the ranchers refusal to sell their land may be influenced by borax mine magnate Stevenson Jonathan Hale, who wants more money than the government is offering for his Atlas Borax Mine. To prevent ranchers from selling their land to the army, Stevenson and his men embark upon a plan of sabotage that makes it appear that the army fliers are employing ruthless tactics to force the ranchers into selling.Influenced by Stevensons covert agitation, the ranchers are driven to armed resistance when Gabbys nephew Jimmy Billy Lee is killed in an explosion caused by Stevenson. As the ranchers prepare to barricade the town, Gene rides to the rescue with proof that Stevenson was responsible for the explosion and the sabotage. Angered by the treachery, the ranchers, led by Gene in an armored truck, ride to the Atlas Borax Mine and bring Stevenson and his gang to justice. ........

Source: Wikipedia