Dr. John Meredith has been driven from civilization by the criminal activities of his twin brother Bradley Meredith. With his infant daughter, he settles in the African jungle, where his ability to cure the native ills has resulted in his virtual control of the Masamba tribes, who possess vast diamond mines coveted by a gang of crooks. They use Shamba, a witch doctor jealous of Dr. Meredith's influence over the tribe, to further their schemes. They lure Dr. Meredith away from the jungle, and he is murdered by "Slick" Latimer. The natives believe that a sacred amulet is the secret of Dr. Meredith's power, and Shamba attempts to kill Nyoka, Meredith's now-grown-up daughter, to obtain the amulet (which actually contains the secret to the entrance of the Caves of Nakros). Jack Stanton rescues her and assists her in her efforts to recover the amulet. Latimer works with Shamba, and with Bradley Meredith, who poses as his murdered-brother so successfully that even Nyoka does not realize the deception.

Wild Bill Tolliver and Missouri Benson ride into the territory of New Mexico to search for Bill's father, Henry Tolliver, who disappeared while prospecting. They discover that a ruthless outlaw leader, Jonathan Kincaid, has joined forces with Carl Engler, a renegade European general, and Kincaid owns a giant gold mine and uses captured Mexican patriots, and others, to work as slaves on his property. Bill and Missouri become friendly with Consuelo Romeros, an agent for the Mexican government, and they learns that Bill's father is among the prisoner/slaves in the mine. After freeing his father, Bill sets out to smash both the slave-mine operation and Engler's attempts to overthrow Benito Juarez, the legal president of Mexico.

Miserly old Anton Benson once recovered a treasure in gold from a sunken Spanish galleon, and in his greed murdered anyone who got in his way of keeping it. Now his family is gathered at his estate, Bensonhurst, and they are all searching for the treasure, which is hidden somewhere on the estate. Also looking for the gold is a masked killer called The Iron Claw, who murders one member of the family and lets the others know that they'll be next.

A sea captain about to be hanged for a murder he didn't commit is rescued from the gallows by two of his crewmen. They head for the island of Pulinan, where they believe the real murderer--the captain's former partner--is hiding so the captain can clear his name. As it turns out, their troubles are only beginning.

Greedy oil speculators, led by Morgan, are trying to force Tiger Woman and her band of warriors from their jungle home. Allen Saunders of Inter-Ocean Oil wants to develop the oil, too, but fights with Tiger Woman to stop the bad guys.

Government agents battle a gang of Nazis who are trying to use the Orotron machine, which can turn seawater into gold.

The evil and masked "Gargoyle" is sabotaging all of America's industrial plants. It is up to the Spider to save the country.

A mysterious detective called The Masked Marvel battles Japanese saboteurs intent on blowing up America.

Crime lord Jim Belmont escapes FBI custody and begins a reign of thievery that is thwarted at every turn by Jerry Blake, the FBI's Operator 99.

Mine owner Jackson Decker orders his manager to obtain Tom Bailey's milling machinery no matter what the cost. When Bailey is found murdered, suspicion naturally falls upon the mine owner and his son, a Canadian Mountie, is ordered to find the real culprit. He joins forces with a French-Canadian constable, Bailey's beautiful daughter and a phony palm reader to learn the truth and discovers a secret gold mine, a double-crossing casino owner and a forger at the bottom of the conspiracy.

At the Bainbridge Research Foundation, Professor Franklin Arnold, displays his creation, the Metalogen Man, a robot, to Professor Ernst and three other colleagues. Shortly afterward, the three associates are killed by Thor (Ray Corrigan, in his for-rent ape suit), a huge ape trained by Ernst, and Arnold, his daughter Babs and Ken Morgan, a representative of the company for whom the robot was made, find it has been stolen. Their 15-chapter search for Thor, the robot and Ernst leads to a series of cliff-hanging adventures as Ernst strives to gain control of the robot and the supply of metalogen needed for its production.

Evil Hassan slips back into his native land of Ahad and plots to overthrow his twin bother, Kasim, who has just been crowned the Caliph. Hassan enlists the aid of the chief Chamberlain, Faud and they send several henchmen into the royal palace, who then knock Kasim unconscious. Faud and Hassan dispatch a couple of different hirelings to take Kasim into another part of the town and murder him.Kasin comes to and gets away, but has been wounded. Omar, a beggar, takes Kasim to his home and nurses him back to health. But, it takes a few weeks for Kasin to get healthy and, by that time, Hassan has a firm grip on the duties of a Caliph. In a storeroom, Kasim finds a coat of mail with a great hawk emblazoned across the chest and promptly decides this is the costume he will wear while fighting to get his old job back. Meanwhile, the Emir of Telif shows up with his daughter, Princess Azala, with the intent of marrying her off to the local Caliph. They do not know that the current-Caliph on the royal-throne is the evil twin-brother of the man they think he is.

A Martian spacecraft crash-lands near the observatory of Cyrus Layton, designer of Earth's first spaceship. The survivor, forerunner of an invasion, can assume the form of any earthman. Calling himself the "purple monster," the humanoid invader sets about gaining control of Layton's rocket project. Opposing him is Craig Foster, former Secret Service man, who episode by episode tries to thwart the monster's attempts to acquire rocket components. Will Craig ever suspect that his closest associate is really the monster?

Girl looking for father who disappeared years before in a jungle, finds herself battling greedy civilized people and savages alike.

Homesteaders are moving into the valley settled many years ago by rancher Craig Dolan. He wants to keep them out by legal means but his nephew Bart brings in outlaws to drive them out. The Lone Ranger is on hand to help the homesteaders battle Bart's men as he overcomes traps, ambushes, burning buildings and other obstacles in his attempt to bring peace to the valley.

Wagon trains are not making it to Oregon and Jeff Scott has been sent to investigate. Morgan, the representitive of an eastern syndicate, controls the fur trade and does not want the area settled. So he sends his men lead by Bull Bragg to stop the latest wagon train. Scott is quickly on to Bragg and repeatedly captures him only to have him escape before he can reveal whom is responsible for the attacks.

The Shadow battles a villain known as The Black Tiger, who has the power to make himself invisible and is trying to take over the world with his death ray.

Three government aviators called the "Flying G-Men", one of whom is disguised as "The Black Falcon", fight to protect the US and its allies from an enemy spy ring and to avenge the death of the fourth Flying G-Man.

A short plot summary finds Wild Bill Hickok (Bill Elliott), the U.S. Marshal in Abilene, Kansas, opposing the Phantom Raiders, a gang of renegades raiding the cattle drives over the Chisholm Trail from Texas to Abilene. Hickok organizes the boys of the town into the "Flaming Arrows" to assist him. Finally, in the 15th chapter, "Trail's End", Hickok, the "Flaming Arrows" and army scout Kit Lawson (Kermit Maynard) combine to put an end to the Phantom Raiders.

A 12-episode serial in which Tim Tyler goes to Africa in search of his father in gorilla country. He meets up with Lora, who is after Spider Webb who has framed her brother. Webb causes the death of Tim's father, but is eventually tracked down.

A 15-episode serial in which Buck Grant, the Phantom Rider, helps rancher, Mary Grayson, fight off a band of outlaws out to seize her property.  

A 15-episode serial in which our hero, Jim Dorn helps hide Jean McNain from a man she can implicate in a murder.

A 12-episode serial in which scholastic sports star Frank Merriwell leaves school to search for his missing father. His adventures involve a mysterious inscription on a ring, buried treasure, kidnaping and Indian raids. He saves his father and returns to school just in time to win a decisive baseball game with his remarkable pitching and hitting.

An expedition arrives on an uncharted jungle island to rescue the local natives, led by a jungle boy, from a volcano that is about to erupt.

The US marine corps must battle a would-be world conqueror who uses electricity as a weapon.

A variety of people are searching for a long-hidden treasure somewhere on an island.