Texas Ranger O'Brien has an outlaw twin brother. When his sibling is killed, O'Brien assumes his identity in order to infiltrate a gang of stagecoach robbers.
Things get under way when US marshal Tom (Starrett) finds himself in the midst of a range war. The villains are a band of rustlers who play both sides of the confrontation against one another, the better to move in and claim all the livestock.
Johnny and Alibi try to straighten out a hostile young boy whose older brother was a notorious stagecoach bandit. When a gang of thieves try to strong-arm the kid into revealing the whereabouts of the stolen loot, Johnny and Alibi come to the rescue. There's a cursory romantic subplot involving heroine Mary and Barstow.
A pair of crooked deputies steal a gold shipment, murder a young boy's father and pin the blame on a cowboy. The murdered man's son and his dog set out to prove the cowboy's innocence.
Briefly switching gears in 1942 and 1943, western star Charles Starrett made a handful of "northerns" in which he played a Canadian mountie. In Law of the Northwest, Steve King (Starrett) supervises a road-construction project designed to transport war materials to the Aleutians. Problems arise when a crooked contractor decides that his interests are more important than the war effort.
Local "patriot's league" leader secretly kills off ranchers, buys up their estates, which are undermined with tin ore; Marshal and singing cowpoke team up to find villain and motive.
Johnny Williams (Johnny Mack Brown) returns to his home town of Beaufort, and finds himself when being chased by banker Henry Stevens (Tristram Coffin), Grangers Association head Les Travers (Ed Cassidy as Edward Cassidy) and real estate agent Frank Wilkins (Ted Adams.)
Johnny Mack (Johnny Mack Brown ) is hired by Lois Benton (Virginia Carroll) as a hand on her ranch, formerly run by Daley, who is in jail on a payroll theft charge. Despite the warning for foreman Rusty Steele (Raymond Hatton), Johnny sees real estate agent Kirby (Bill Kennedy), who wants to buy the Benton ranch. When Johnny refuses to align with Kirby, he is forced to knock out henchman Moran (Marshall Reed) in a fist fight. Rusty finds on henchman Harris (Forrest Matthews), when he is caught spying on the ranch, half a map revealing the location of the missing payroll.
In California in 1848, Brunton through his stooge Sheriff is evicting the Mexicans from their ranches. Major John Freeman and his troops arrive to investigate. Keeping his troops hidden and appearing out of uniform, he takes up the fight against Brunton. He helps a rancher who has been evicted before his taxes were due only to find him murdered and this leads to the showdown between Brunton's men and the soldiers.
Bob Carson and sidekick Grizzly take a job driving a stage for a line that is being repeatedly robbed. The culprits place a large box on the stage in which Runt can hide and steal the gold without the driver or guard knowing it. When Bob realizes what is happening, he replaces Runt in the box in hope of catching the outlaws.
Arriving in Arizona, the band members discover that the hotel is haunted and that it properly belongs to young Jimmy Benson (Curtis), the nephew of the previous owner. The "ghosts," however, turns out to be a trio of confidence men, Zeke Winslow (Guinn "Big Boy" Williams), Noah Jones (Raymond Hatton) and Slim Jensen Victor Potel, who are hoping to buy the place themselves.
Doan is trying to get control of the valley by having his night riders drive the ranchers out. Jack Benson hires on at the Williams ranch, the one ranch Doan must have. When Benson learns that Doan is the boss of the night riders, he joins up with him. He has a plan that both saves Williams' ranch and also brings Doan to justice.
Lightning Bill Carson and sidekick Magpie are after Burrows, the man that killed a friend of theirs. Burrows is after the Arden ranch and his gang are rustling their cattle. Bill is robbing Burrows while posing as the mysterious Phantom and it's not long before the two collide.