Ethan Allen and the Green Mountain Boys are at war with the ruthless tax collectors, a bunch of outlaws, more Robin Hood than the Dalton gang; when the authorities start to pin their misdeeds on them, Hawkeye must sort it out.
Hawkeye and Chingachgook find Wenatchgo, an old and respected medicine man, wandering in the forest; they discover that the elderly man has been driven out of the tribe by a younger and ambitious rival.
Cowboy Roy Rogers travels to Rancho San Angelo, a territory on the American-Mexican border, to help Cookie Bullfincher investigate some mysterious deaths around a silver mine. Roy's suspicion of mine manager Gus Ulrich is shaken by the unexpected arrival of Western author Lee Madison, who advises Roy to read one of her books to help him solve the murders. Meanwhile, Cookie follows Ulrich to the mine and discovers a complex scheme.
In Oklahoma, after the death of ranch owner Sam Talbot, niece Jan (Carol Hughes) learns with dismay that her uncle has left the ranch to 12-year-old Duke (Lanny Rees), a ward of Sam's foreman. In town, newspaper editor Roy Rogers (Roy Rogers) is left a book from Sam with a note asking him to investigate his death. Roy clashes with reporter Connie Edwards (Dale Evans), who writes an article about the suspicion of foul play, but soon Roy must protect Duke from mysterious attacks.
In the 18th century, American artist Jonathan Adams (Scott Brady) is working in Mohawk territory, where he paints the local scenery. Before long, he meets and falls in love with Native American woman Onida (Rita Gam), but the couple's happiness is interrupted when land tycoon Butler (John Hoyt) deviously pits incoming white settlers against the Mohawk people. Jonathan and his lover are caught in the middle of a violent feud, and the natives become suspicious of the American living among them.
Aging rancher George Washington McLintock, a wealthy self-made man, is forced to deal with numerous personal and professional problems. Seemingly everyone wants a piece of his enormous farmstead, including high-ranking government men, McLintock's own sons and nearby Native Americans. As McLintock tries to juggle his various adversaries, his wife, who left him two years previously, suddenly returns. But she isn't interested in her husband -- she wants custody of their daughter.
Adopted by the wealthy rancher Arch Strobie, orphan Owen Daybright (Burt Lancaster) grows to be a respectable foreman on Strobie's ranch. Strobie's natural son, Lee (Robert Walker), is jealous of Owen and finally finds a way to undermine his upstanding brother. When Lee conceives an illegitimate child with Lily Fasken (Sally Forrest), who refuses to name him as the father, he tells her revenge-minded brothers that Owen is to blame, hoping they'll take his half-brother out of the picture.
When young Betty Marsh (Mary Russell) learns that her archaeologist father is missing, she calls upon cowboy heroes the Three Mesquiteers -- Stony Brooke (Bob Livingston), Tucson Smith (Ray Corrigan) and Lullaby Joslin (Max Terhune) -- to rescue the man. This leads the trio to a treasure map and, ultimately, to a treacherous place called the Whistling Skull: a rock formation occupied by a Native American cult, mummies and a madman who has been pulling the strings all along.
When the esteemed Judge John Grey (Harry Shannon) finds himself on trial for the robbery of a local bank, singing cowboy Roy Rogers (Roy Rogers) comes to his friend's aid. Rogers suspects a frame-up, and the trail of clues leads directly to the crafty Belle Bonner (Ona Munson), a woman whose disreputable saloon has recently sparked the judge's ire. To clear Grey's name, Rogers must convince the townspeople of his innocence -- and face off against Belle and her gunslinging henchmen.
Detective Tom Wade (Tom Tyler) has to investigate the truth behind a robbery and murder of a bank president that's being blamed on Tom's brother, Ed (Bob Terry), who is nowhere to be found. Also trying to find out what happened is the bank president's daughter, Celia Chandler (Lois Wilde). She initially suspects Ed, who is actually being held hostage to prevent him from talking. Eventually, Celia realizes that the culprit may in fact be someone who purported to be her father's friend.
A gang of poachers must be stopped as they kill and sell game out of season. Roy figures out who the culprits are and goes undercover to investigate further.
Horse trader Roy Rogers has plans to breed his prize mare with legendary stallion Golden Sovereign. Unfortunately, scheming nightclub owner Brett Scoville (Jack Holt) has his eye on the same stud and steals the horse. Sovereign breaks free, however, and mates with Rogers's mare, eventually producing a spirited colt that Rogers names Trigger. When Sovereign is accidentally killed, Rogers is blamed for the crime, and he and Trigger must escape the law and track down the real killer.