Initially resistant to becoming a lawman, Wyatt Earp has a change of heart after seeing the sheriff of Ellsworth, Kansas murdered in cold blood by the inebriated brother of town scourge Ben Thompson.
Earp jails Ben Thompson in the hope that his mentally unstable brother Bill will attempt a jailbreak, but the Marshal underestimates the misguided and naive ruthlessness of young Abbie Crandall, who is also determined to help Ben escape.
Wyatt Earp's insistence on patiently stalking the Thompson brothers with a pair of Indian scouts (rather than a posse) doesn't set well with some influential Ellsworth citizens who demand immediate pursuit and capture of the two fugitives.
A quick-tempered former Confederate officer with a grudge against Wyatt Earp threatens to assemble a mob and destroy Ellsworth if Wyatt is not immediately stripped of his badge and run out of town.
Wyatt leaves Ellsworth and becomes the Marshall of Wichita. His first challenge is a group of local vigilantes so intent on hanging a local Faro dealer that they are concealing evidence that he was acting in self-defense.
Bennett hires a gunman to shoot Earp who brags he has faced down Earp before. However, Earp doesn't know him so he suspects there is more to the gunman's story. After trying to determine who the gunman is, Earp decides he must face him.
Earp is blamed for the back shooting of the saloon owner Bennett after exposing his crooked games. Earp is the only person to use copper jacketed bullets in Wichita which is what was dug out of the wounded Bennett's back.
After Earp kicks Bennett out of Wichita for a crooked Faro game, Bennett hires the killer Manon Clemens to kill Earp and have his cowboys tree the town. Earp uses trickery to defeat Clemens who kills Bennett for deceiving him.
John Wesley Hardin comes to Wichita to revenge Earp running his friend Clemens out of Wichita. Hardin has told his wife he is happy to leave and continue to Nebraska but he has several gun tricks one of which he plans to use on Earp.
Wounded bank robber Clem Parker and his girl Bonnie Dawson want no part of Tarp Anders' brash gang of thieves, but Wyatt isn't sure whether to believe Bonnie's story that the Anders gang plans to rob the Union Bank without Parker.
Texan A.H. 'Shanghai' Pierce tries to use his money and influence to make Wichita an open town again by hiring a well known actress to get to Earp. Next, after a card game he tries offering Earp a partnership in the saloon he bought.
Earp is pushed into being chairman of the Wichita baby contest run by the local women. When a broke, hungry woman with a baby arrives in Wichita, the doctor and Earp enter her in the contest but find a hidden rule may ruin their plans.
Local gamblers feeling pressure from Marshall Earp concoct a scheme to force the mayor of Wichita, Kansas to get rid of Marshal Earp. A fearless journalist backs Wyatt despite pressure from gambling interests.
An immature rancher's son forced to sell a herd at at a low price tries to make up the difference in a poker game while drunk and loses. Earp refuses to help since no law was broken so the son takes matters into his own hands.
The young runaway son of a powerful railroad executive wants to become a gun-toting cowhand, but Wyatt manages to teach him some far more important lessons about honor and self-reliance.
A little man with a brash manner and a large gun visits Wichita hoping to interest Marshall Earp in joining a Wild West Show. He provides Earp with a new gun that becomes a Wyatt Earp trademark - his Buntline Special.
Earp has been using sanitary laws to close crooked saloons as Ben Thompson comes to Wichita to open one. Ben feels a debt of gratitude toward Earp but it causes problems as the rest of the saloon operators have men gunning for Earp.
Earp takes an interest in Mamie Perkins but there is something amiss in the relationship even though his friends hope they marry. Earp learns she loves another man who needs Earp's protection from Fog MacMurray's gang of cattle rustlers.
Earp kicks a crooked gambler out of Wichita so three saloon owners decide they are tired of the pressure. They decide to hire two gunmen to assassinate Earp but he gets wind of the plot. Earp brings in some special outside help to stop it.
Bill Slocum is accused by Duke Wilson of rustling. They take him in Wichita with plans to lynch him outside town but Earp stops them. Slocum is put on trial while Earp does some investigation which produces a major surprise for the jury.
Two Indians who have helped Earp previously, are being held by a renegade selling rifles to the Indians. They are in the Oklahoma Territory so the Army has asked Earp to go in as a US Marshal to rescue them. He does but as a doctor.
Earp returns to Wichita to find a crooked gambler has been given a saloon license by his deputies. Murdock wants the license revoked as Earp's desk is found to contain a $300 bribe framing Earp who has to give up his Marshal badge.
Earp closes a show because the men attending are being ripped off by the girls in it. The owner wants to get even with Earp. He decides to attack the stars of a competing play hoping to trap Earp on his own terms but Earp has other plans.
Big winners at the Keno House are being killed and robbed on the way back to the their camps. Earp is unsure if it is crooked casino owners or someone else doing it. A volunteer comes forward to solve it but Earp is then faced with a mob.
George Peschauer hates Earp and was kicked out of Ben Thompson's gang for his ruthlessness. He is trying to sell an Englishman a ranch loaded with rustled cattle but a nosy female hotel owner is trying to protect the likable Englishman.
The Kansas Kid is wanted by the Kingman Sheriff for robbery, murder, and wounding one of his deputies. The Kid returns to his parents home where Earp arrests him. However, there is a question of his guilt and the intentions of the Sheriff.
Horses are being stolen around Wichita pushing the ranchers to want a necktie party. Their sights are set on a group of gypsies on Gus Cassen's property. Gus is an old friend of Earp who denies guilt but evidence forces his arrest for it.
A respected member of the community shoots a thief and is hailed as a hero. However, it is found that he himself is wanted for being in the James gang. Hs wife is coming to join him forcing Earp to arrest him when he hoped for a new start.
When a man is murdered in Wichita, Earp wants the Newton gang for it but Allen Pinkerton is interfering and more interested in recovering some stolen money. Due to Earp's actions, the Judge at Pinkerton's request takes Earp's badge.
A suffragette invited to Wichita by Murdock's wife to give a speech is interrupted by men supporting Senator Teague who is against women voting. Earp is caught between both sides trying to control the dangerous fights between them.
Earp is forced with the help of Mr. Cousin to go into the rough Bushwacker area to track down a man wanted for murder. The man says he is innocent and Earp begins to question his guilt when the man never attempts to kill him or Rr. Cousin.
Two ranchers have started a range war that is spilling into Wichita where innocent people could be killed. The granddaughter of one is involved plus she takes an interest in Earp. He is more concerned with a way to stop the war in Wichita.
Earp learns Masterson has dropped out of school and is a scout for the Army. He is being threaten by the killer Sgt. King over a woman using Bat as leverage to keep King away. Earp tries unsuccessfully to talk Bat into leaving her.
