Bronco Layne goes to the town called Trinity to help his friend Jim O'Neil who is about to be hanged for the murder of a ranger, Colly Smith. Layne investigates Duke Rhein, a cattle owner, and finds out that he and his thugs are smuggling opium across Jim O'Neil's ford in the Rio Grande river by packing it inside hollowed out cattle horns. Duke had also killed the ranger who knew too much and framed Jim O'Neil. Bronco tries to stop O'Neil's execution but finds out that Jim's wife and daughter are held hostage. When he finally finds them, Jim O'Neil can then say what he knows and the guilty are brought to justice.; In the Arizona territory, Bronco Layne comes across a cavalryman shot dead. At Fort Grant, Colonel Burton tells him he suspects of someone in his fort working for the crooked Tucson Ring who is paying soldiers to desert and is selling worthless supplies to the army. The murdered soldier was a deserter who had changed his mind and was thus finished off with the complicity of the treasonous Sergeant Flint. So Bronco then decides to infiltrate the gang, but is revealed by Sergeant Flint. Bronco manages to narrowly escape and then lays a trap of his own for the criminals to fall into.; Small Bear wounds and is wounded by a mountain lion. The animal, not able to hunt, later attacks the Cheyenne tribe and it's horses convincing them that it is a "spirit cat". Small Bear feels responsible and still recovering from his wounds and against the Chief's orders, for the sake of his tribe and his honor, hunts the animal by himself. He slays it with his spear lodged between rocks and then everyone congratulates him.