A young girl journeys to Africa to find her father, an explorer who vanished in the jungle.

Two prospectors, one the father of Skye "Lightning" Bryce and the other the father of Kate Arnold, find a large gold deposit belonging to an Indian tribe. They head for home but each sends a note to their respective off-springs advising them of their good fortune. One of the fathers conceives a plan of taking a dagger and wrapping a piece of string around the blade, after which he prints on the string with a lead pencil, the exact location of their find. If something happens to them, the string goes to the son and the knife to the daughter. That night an Indian approaches their camp and blows some mysterious wolf powder which causes a man to see wolves in place of human beings. Lightning's father see his partner as a wolf and stabs him to death; later he is brought into town in a dying condition but before dying, hands the knife and the string over to the sheriff with instructions to deliver to Lightning and Kate.

An expedition sets off for the last land of Mu, where legend has it that a killer death ray is emitted from the eye of a golden idol.

Rex, a wild stallion, and Rinty, a police dog, are pals. Their master , John Sheldon, is framed for murder, and Alice Ingram plans to race Rex for money to pay for John's legal defense. Meantime, Frank Nolan, who has falsely accused John, sets out to steal Rex for himself.

An intrepid reporter and his loyal friend battle a bizarre secret society of criminals known as The Vampires.

Two safaris enter the African jungle intent on finding a white girl who is the heiress to a fortune. One safari, led by Jungle Jim, wants to make sure she gets the news that she is now a rich woman. The leaders of the other safari want to kill the girl so they can try to get hold of her inheritance.

The misadventures of a suburban boy, family and friends.

A gang of street kids work with the FBI in their attempt to find and rescue their leader's father, a scientist who has been kidnapped by a terrorist group.

Crash Corrigan, a recent graduate of Annapolis, and Diana, a go-getting reporter, join Professor Norton for a search for the source of a string of earthquakes, Atlantis. They ride Prof. Norton's rocket submarine searching the sea and little Billy Norton, the professor's son stows away, of course. When they find Atlantis they are caught in a war between peaceful Atlanteans, note their white capes, and war-monging Atlanteans, note their black capes. After many harrowing moments for Crash, Diana, Prof. Norton and Billy, they barely get away with their lives when they escape a tower of Atlantis raised to the surface for the sole purpose of dominating or destroying the Earth (Which one depends on the compliance of the upper world dwellers.)

A group of street kids battle a terrorist gang led by a Japanese spy.

Police detectives battle the League of Murdered Men, a gang of resurrected dead criminals.