Tom discovers the bodies of several Sioux who have been massacred, and reports the incident to the local Indian agent. The agent is shot by an arrow while going to investigate, and before he dies appoints Tom as his temporary successor. The killings have been ordered by the ruthless local Army lieutenant, who plans to instigate war between the whites and the Sioux in order to obtain gold in the Black Hills. An ambitious young female photographer also becomes involved in her search for a big story.
Nora Sutton asks Tom to take her to Clifford Henderson's house. After he does so, she calmly takes out her gun and shoots Henderson dead. She refuses to say why she did it or even ask for an attorney, so Tom is appointed to that role, and he determines to get the answers himself.
In Medora, Tom meets Theodore Roosevelt, who has come with the intent of buying a ranch, though he is warned that the big cattlemen in the area don't want to share the open range. With Tom's help, Roosevelt decides to come to the assistance of a widow and her daughter whom the ranchers want to force out. He decides to buy half her land so that she can stay on.
Tom accompanies a Sioux chief and his daughter to Chicago to meet with President Grant for peace talks, but a faction of the tribe does not want peace and is determined to stop them, as are some white men who have their own vested interest.
Tom is appointed deputy sheriff of Casa Grande while his friend, gubernatorial candidate John Brice, is visiting. When Brice is shot and seriously wounded, the town is quick to blame hotheaded rascal Toothy Thompson, but Tom prevents them from lynching him. Because of this, Toothy is so grateful to Tom that he wants to follow him everywhere and defend him against every slight, which starts to interfere with Tom's job in finding Brice's real assailant.
Tom tries to help a young brother and sister and their sheepherder father, who are being threatened by a local cattle rancher. When the rancher's foreman kills the boy's dog, he and his sister vow revenge, and Tom hopes to prevent bloodshed. He soon learns that the ruthless one is not the rancher but his daughter.
Riding through Leadville, where a ruthless group of thugs has been forcing out or killing anyone who stakes out rival mine claims, Tom comes across a deaf-mute girl who's father has just been murdered by them. The killers think she can't identify them, but Toothy Thompson, who knows sign language, can communicate with her and finds out she can. Toothy and Tom are both deputized by the local sheriff, and Bronco Layne also arrives in town to help out.
When Tom brings in the bodies of two outlaws who shot each other on the trail, many in town assume him to be a gunslinger as well, and because of this several foreigners try to hire him to kill Harry Bishop, the owner of the mine they work in, claiming that he cheated the rightful owner out of it. Tom winds up accepting a job as Bishop's lawyer instead. But he has regrets after the judge rules in his favor, feeling there is more to the story than what was presented.
The three Benbow brothers are not trusted in the town of Sand Springs, but Tom hopes to keep the youngest one out of further trouble. When the boy accidentally shoots a man, the judge puts him under the supervision of Tom and the local banker. Trouble occurs when the brothers come into the bank and find the safe cleaned out and the banker dead. Tom hopes to find them before an angry posse does.