Bullet Code (1940)

Protecting himself in an attack by rustlers, Rancher Steve Holden believes he has killed one of the attackers, young Bud Mathews, who in reality has warned Holden of the rustlers' approach. Unaware that Mathews was actually killed by rustler boss Cass Barton, Holden heads out to Mathews' home town where he plans to tell the boy's family of his death but instead uncovers a plan by a local businessman to force Mathews' father out of his ranch.