Earp's cousin Nate has been murdered by stabbing putting Earp in a frenzied mood. He has learned the man who did it was riding a Circle Diamond outfit horse and the outfit is now in nearby Oklahoma driving a herd. Against Gibbs wishes, Earp decides to go alone undercover as a drifting cowboy from Alabama to join the outfit. He finds a couple of Circle Diamond hands ahead of the herd in a gunfight with freighters. He is able to settle their differences leading to a potential offer of work with the Circle Diamond outfit. The trail boss Tim Corkle puts him to work with the hothead cook. A near knifing by the cook leads to Corkle putting Earp to work with three men lead by Jumbo riding tail end Charlie or drag on the herd. Earp soon learns Jumbo has a knife like the one used to kill Nate but he claims to have won it in a poker game from someone. When Jumbo is wounded by Corkle, Earp learns Jumbo knows who he is and that he suspects Corkle and his confederates Red and Turk are also outlaws. Earp decides to use Red and Turk to put pressure on Corkle as well as each other to find the truth.
—Anonymous