Gene and Frog, out to stop a bunch of cattle rustlers, assume the identities of what they believe to be dead bandits, which soon gets them in big trouble.
A crooked real estate manipulator sells worthless land on mortgage to flood refugees, then tries to profit by reselling the land to the state, committing murder in the process, as the Three Mesquiteers work to bring him and his gang to justice.
Ace Beldon is in prison, but with his stolen bonds not recovered, Capt. Saunders has an idea. He sends Graham to prison and has him and Beldon break out. With Ranger Raymond assisting, they make their escape and get to the hangout run by Stone. But the plan starts to go awry when Sam overhears Graham talking with the Captain and reports back to Stone.
Unable to legally capture and sell a herd of protected wild horses, corrupt rancher Rance Macgowan uses his trained killer horse, Volcano, to substitute for the real leader of the herd and cause havoc and death among the ranches. With the government about to drop the restrictions on rounding up the herd, the Three Mesquiteers find themselves in the middle of the controversy after their friend, Sheriff Miller is killed by Volcano.
As the sheriff of a small western town, Autry sings his way into a relationship with Eleanor, a singer from a Chicago nightclub who earlier witnessed a murder.
The Commandant is making life rough for the colonials in Spanish California. While trying to help, Zorro is charged with the murder of the new Governor, but in the end he triumphs over the evil Commandant.
In his film debut Ritter is sent to investigate miners being killed and their mines confiscated. The culprit is Evans and after Tex joins the gang, he is sent to kill two more miners. When Estaban is killed, Tex is put on trial for all three murders.
At the Texas Centennial in Dallas Autry confuses two girls by being himself and his own stunt double. When cowboy star Tom Ford disappears, Wilson gets his double Gene Autry to impersonate him. But Ford owes gangster Rico $10,000 and Rico arrives to collect. He fails to get the money but learns that Autry is an impersonator and now blackmails Wilson and his movie studio. Original version runs 71 minutes, edited version runs 59 minutes.
The Government sends Dean, Baxter, and Gordon to investigate a series of train holdups. Travis is behind the robberies and they are soon on his trail. When things get hot, Travis has a plan of double-crossing his own men that will enable him to keep not only his gold but also the money it is insured for.
A Professor has an invention that will bring down planes causing them to crash and Dawson is forcing him to use it on those carrying money. When Tim arrives to investigate he is mistaken for a noted outlaw. So he assumes that identity to force Dawson to make him a partner. But just as a plane bringing Tim help is arriving, his true identity is revealed and while he is a prisoner, Dawson forces the Professor to start his machine.
The arrival of the telegraph put Pony Express riders like John Blair and his pal Smoky out of work. A race will decide whether they or stageline owner Drake get the government mail contract.
The story is set in the British province of New York during the French and Indian War, and concerns—in part—a Huron massacre (with passive French acquiescence) of between 500 to 1,500 Anglo-American troops, who had honorably surrendered at Fort William Henry, plus some women and servants; the kidnapping of two sisters, daughters of the British commander; and their rescue by the last Mohicans.