Lefty Bill Ranger accepts an offer of employment from Menneval, a man feared throughout the territory. Monitoring the activities of rancher Peter Crosson and his son Oliver in California, Ranger sees a large mountain lion, pursued by a pack of wolves, and a young man on horseback armed with only a knife. Later, he sees two disreputable, heavily armed men enter the Crosson range, aiming to rustle cattle. When Ranger sees them again, they are on foot, wounded and fleeing for their lives. Has Ranger seen the work of the lightning of gold?