The Cattlemen's Association has called in the Mesquiteers to find cattle rustlers. They get Tex Riley to pose as Stony so Stony can arrive posing as a wanted outlaw. This gets Stony into the gang of rustlers and he alerts Tucson and Lullaby as to the next raid. But Hartley is on hand and unknown to anyone is the rustler's boss and he joins the posse with a plan that will do away with the Mesquiteers.
The local school is causing Hoppy problems. First Bar 20 cattle are stolen when Hoppy investigates a problem there. Then the new teacher arrives and disrupts the routine of the Bar 20 hands. Later with the Bar 20 hands at graduation, the rustlers are poised to strike again. But there is dissension among them and this will lead to the break that Hoppy needs.
Knowing that is contains valuable helium gas, a gang of bad guys first tries to purchase the ranch which Gene straw-bosses. When that fails, they lay a hidden pipeline to snag the gas.
Mary Smith decides after a lifetime of being a shut-in to do something wild while her father is out campaigning for the presidency, so she takes off for the family's home in West Palm Beach and inadvertently becomes romantically entangled with earnest cowboy Stretch Willoughby. Neither the dalliance nor the cowboy fit with the upper class image projected by her esteemed father, forcing her to choose.
Jack has been called in to investigate stage robberies where the stolen gold bullion mysteriously disappears, He finds the Professor, an elderly ex-con, and convincing him they used to work together, gets the Professor to get him in to the gang. Now posing as an outlaw, he learns what the Professor does with the bullion, but he is in trouble when his true identity is revealed.
Gene takes care of three tough kids sent west from Chicago after their father died and left them a cattle ranch. They help him catch a bunch of rustlers.
After gold shipments from a mining town have been hijacked, the three Mesquiteers buy a plane to fly the gold out. The owner of the shipping line brings in Eastern gangsters to thwart them.
Tex has been sent to investigate the theft of government provisions along the border. Kildare is the leader of the outlaw gang and has his men posing as Indians. He has already killed the incoming Marshal and assumed his identity. When Tex asks too many questons, he plans to get rid of him also.
The Shadow and his outlaw gang have control of Durango Valley. Keene Cordner arrives, and with the help of Tanner becomes a second Shadow in his attempt to round up the gang.
Scanlon is pulling off a land swindle by selling lots in a ghost town claiming the power company is bringing in a line. As a bonus he throws in shares in a worthless gold mine. Gene is on to Scanlon and tries to get him to buy back the deeds by salting the mine with gold. But when a new vein is really discovered Gene has to stop the sales but is trapped in the mine by Scanlon's men.
Death stalked Garou's Landing, in the Canadian frozen north, but who was the killer who murdered two men and left them huddled in the snow. Sergeant Renfrew (James Newill, of the Royal Canadian Mounted Police, accompanied by his dog, Silver King (Silver King the Dog), and Kay Larkin (Terry Walker) the daughter of the man, Andrew Larkin (Robert Frazer) accused of the crime, sets out to solve the crime and bring the real killer to justice.
It's cattlemen versus sheepmen and Trigger Gargan appears to be the leader of the gang causing the trouble. But unknown to Ranger Tex Lawrence, the respected town citizen Barrow is the boss and is tipping off the gang as to the Ranger's activities.
Caldwell and Nixon have their men rob the stage and then critcize the Sheriff for not catching the robbers. With her father the Sheriff under pressure, Mary sends for Hoppy who finds the stolen money and sets a trap to bring in the entire gang.
Hoppy's friend Dennis owns a rich gold mine. Frazier who owns the adjoining mine and wants the Dennis mine, has Dennis killed. Hoppy steps in to take over running the Dennis mine and learns Frazier's men sneak into and work the Dennis mine at night. Hoppy captures one of Frazier's men only to be captured in return by Frazier and left to die in a burning building.