Mary Keith is a tough, loyal woman who has a hard life living as a homesteader on the range. The local cattlemen have made life even tougher for Mary and her pop. As a result, she has very little faith in the law.
Ever since moving to the range, Mary and her father have had trouble making a living. The cattlemen around them burned their house and their crops more than once. To make it by, Pop Keith stole some steers but in Mary's mind that was barely anything compared to what's been taken from them.
One evening, a federal marshal, a deputy and a cowboy arrived with her father in custody. When the men first came to the homestead, Mary tried to shoot it out with them, but the cowboy tackled and wrestled her into submission. Mary took it upon herself to help her father escape from a rustling charge that she was sure would end in his lynching. Her father was charged with murder as well, but that fact was kept from her.
While she was preparing dinner for the men, her father clandestinely reminded her of the old rifle in the barn and she came up with a plan. She pushed a spur into her leg and blamed the cowboy for causing the wounds. He followed her out to the barn to get lineament. When Mary tried to back off the ruse he forced her to use the nasty stuff, causing her a lot of pain and forcing her to confess. He saw right through her plan, down to the self-inflicted injury, and demanded to know why she did it. Mary pleaded with him to let her father escape, but the cowboy refused.Shortly after, the cowboy and others set out into the desert towards Santa Loma when they were alerted that the lynch mob was near. Mary went along to watch for chances to escape. The group was ambushed by a rancher and his men, and the group took refuge in a rocky cliffside. It was during this fight that Mary learned the truth about her father's alleged murder of the rancher's favorite son.
After the marshal was killed, she feigned a romance with the cowboy to get his gun, but he tricked her and regained his weapon. As their water supply ran low and tempers flared dangerously hot, Mary sided with the cowboy when the others wanted to kill him at a vulnerable moment. The group finally made it through the desert to water. But Pop's enemies also made it through and a firefight broke out. Mary was shot in the shoulder and taken hostage by the rancher's eldest son, who was the true murderer. The cowboy chased after them and Mary was released. After a tense standoff, the real killer was revealed, Pop was unofficially exonerated and Mary rode with them all to Santa Loma...this time willingly.