Sergeant Preston must work to clear King's reputation after a murderous claim-jumper falsely (and publicly) accuses the dog of causing a prospector's death.
A greedy trapper incites an Eskimo uprising and murders an honest Hudson's Bay factor as part of a plot to monopolize the supply of valuable silver fox furs.
The death of an Indian brave leads Sergeant Preston and King to investigate whether sabotage could be the reason for a series of "accidents" that are plaguing the Hog Back Mining Company.
Law-abiding Jim Carver reluctantly offers forgiveness and assistance to his brother Harry, a treacherous ex-convict who is wanted by the Crown for the robbery and murder of an aging trapper.
A self-serving Chilcotte medicine man further endangers his diphtheria-stricken tribe by convincing the chief to reject serum treatment in favor of carrying out superstitious rituals and taking Sergeant Preston as a hostage.
When gold thieves implicate an aging and reformed ex-convict in a robbery, the old man's last best hope for vindication is the unshakable faith of a little girl.
To avert a panic in the mining community of Last Chance, Sergeant Preston and King must move quickly to capture three thieves who used a diversionary tactic to hijack a wagon carrying a gold shipment and a cash-rich mail delivery.
Two thieves steal a coded letter disclosing the location of a fortune in gold, but they find themselves on an ironic quest to find a Bible when they learn that the code involves specific passages in the Scriptures.
Ruthless gold thieves target a rich claim that was reportedly staked by "Windy" Brown, a man with an understanding wife and a reputation as an incurable teller of tall tales.
Claim jumpers Hunch and Shanto are determined to steal a valuable mining claim document that has been concealed inside the violin of itinerant musician Jim Dallas.
Recently orphaned Denny Pickens finds that his Aunt Flora is unreceptive to taking him in, but he gets a chance to prove himself by helping Sergeant Preston in his pursuit of bank robber Cris Darby and his smooth-talking brother.
Sergeant Preston and an overconfident Scotland Yard Inspector trail a fugitive murderer into a wilderness area inhabited by a crazed and bloodthirsty wolf.
An aspiring news photographer with a curious knack for being in the right place at the right time helps Sergeant Preston and King in their pursuit of fur thieves who were responsible for the death of an Indian brave.
Reformed ex-convict Luke Reading is accused of masterminding a series of robberies by a gang of hooded thieves, but he becomes Sergeant Preston's ally when evidence begins to point in another direction.
A ruthless member of a gambling syndicate attempts to affect the outcome of the All-Yukon Dog Race by assaulting the owner of the favored team and attempting to poison his lead dog.
Sergeant Preston offers help to an inexperienced young couple while pursuing thieves who have tapped into the RCMP's telegraph line in order to obtain confidential information concerning gold shipments.
Treacherous sneak thief Milt Strang is saved from freezing by compassionate Yukon newcomer Eileen Mabry. Strang repays the young woman's kindness by attempting to steal her husband's valuable gold claim at gunpoint.
Sergeant Preston must act quickly to prevent a lynching when struggling miner Johnny Johnson is falsely accused of murdering the man who held an overdue note on his claim.
In the Alaskan town of Skagway, Sergeant Preston is assisted by U. S. Marines in his dangerous undercover pursuit of a murderous fugitive and the head of a gold smuggling ring.
After looting a trading post and murdering the owner, two savage profiteers use the stolen food to extort gold from the starving inhabitants of a successful mining camp that was stranded from its supply chain.
While searching for a missing university professor, Sergeant Preston and the professor's son are taken captive by Kutchin Indians and face execution unless Yukon King can quickly find evidence that the Kutchins' "Totem Spirit" is a fraud.
An aging miner finds a rich lode with the help of his newly-acquired English partner, but the sudden wealth makes him the target of his envious brother-in-law and a murderous claim jumper.
Attempting to be the first to reach a new gold strike, greedy prospectors assault a trail-wise competitor, steal his coveted food cache, and cruelly leave him to die from wolves or exposure.
The abusive young widow of an elderly mine owner conspires with thieves to conceal the fact that the deceased man's gentle teen-aged granddaughter may be the rightful heir to his estate.
Concerned for his mother's safety, young Jimmy Greenwood leads murderous fur thieves on a dangerous chase over treacherous and little-used trails with Sergeant Preston and Constable Malloy in close pursuit.
A dishonest promoter with a disdain for "Marquess of Quensberry" boxing rules schemes to abscond with the proceeds from a heavily-attended fight in the remote mining town of Wheelers.
The pusillanimous son of a crusading local newspaper publisher discovers his courage after he is abducted and threatened by the henchmen of the corrupt town boss and his dishonest attorney.
When a greedy mining executive files an unwarranted lawsuit against the claim of two brothers, his debt-laden son convinces one of the brothers to assist him in robbing his father's gold shipment.
A dishonest troupe of traveling performers plans to frame a former war hero for the theft of $17,000 in contributions intended for the families of the American servicemen who died as a result of the explosion of the U.S.S. Maine.
Constable Lee Wayne questions his own qualifications to serve as a Mountie when the brother of his fiancée is involved in a bank robbery and Wayne is unable to take the actions necessary to prevent his getaway.
Mine owner "Windy" Brown's braggadocio and his exaggeration of the size of a gold shipment put Sergeant Preston and King in danger from a pair of sneak thieves.