The Master Key

When a bank executive disappears, he is accused of stealing a fortune from the bank. But his daughter and her criminologist friend set out to find her father and clear his name.

Two expeditions are trying to reach the Lost City of Zoloz -- one headed by Professor Davidson, a scientist who wants to establish an archaeological site, and the other by a greedy treasure hunter who wants to keep the fabled treasures of the city for himself. An agent of a foreign power also wants to establish a secret airbase there, so he stirs up the natives against The Phantom, who has been able to get them to stay peaceful so far. When The Phantom is murdered, his son takes his place and sets out to restore peace to the jungle and stop the agents' and the treasure hunters' nefarious plans.

A police detective is caught up in a plot to steal two million dollars in bonds.

Prior to the United States' involvement in World War II, the masked vigilante Spy Smasher fights Nazi agents operating within the US, led by the treacherous sabotage leader codenamed The Mask.

Mota is a Martian representative, who has come to impose interplanetary law on the Earth (which has become too dangerous); opposing his authority is Kent Fowler, who resists the alien plot, without understanding its details.

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

Beyond Hell's Gate Pass is territory controlled by a man who calls himself King Carter; he uses a variety of schemes to prevent the railroad from being built, for fear it will finish his control of (what he considers) his land.

The obsessive scientist Dr. Miller is working on a matter-transmitter invention called the Paratron; a conspiratorial team of spies and no-goods pursue him to Alaska, trying to steal the device.

Dusty Bates observes some smuggled jewels hidden in a crate aboard a ship; he is pursued by low-lifes when the crate is put ashore.

Jerry Blake (aka Federal Operator 99) teams-up with Joyce Kingston to thwart the plans of escaped crime boss Jim Belmont.

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.

Two British officers are assigned to collect information to convict Captain Kidd of piracy.

Escaped Prisoner 39013 impersonates the rich and influential Horace Granville, allowing him to create a variety of disasters. Fortunately, he is thwarted repeatedly by three daring circus daredevils.

Dr. Mabuse and his organization of criminals are in the process of completing their latest scheme, a theft of information that will allow Mabuse to make huge profits on the stock exchange. Afterwards, Mabuse disguises himself and attends the Folies Bergères show, where Cara Carozza, the main attraction of the show, passes him information on Mabuse's next intended victim, the young millionaire Edgar Hull. Mabuse then uses psychic manipulation to lure Hull into a card game where he loses heavily. When Police Commissioner von Wenk begins an investigation of this mysterious crime spree, he has little to go on, and he needs to find someone who can help him.

Only Episode 7, "The Hooded Helper," of this 20-Episode Serial is known to survive. All other episodes are believed to be lost.

The manager of The Big Circus plots to marry the owner's daughter and gain control of the outfit.

A silent action movie serial.

The forerunner of all serials, What Happened to Mary was a series of twelve monthly one reel episodes, each a complete entity in itself, revolving its immediate dramatic and melodramatic problems within the framework of a single episode and designed more for story and suspense situations than action.

Two marine lieutenants battle a masked would-be world conqueror who uses electricity as a weapon.

A newspaper publisher and his Korean servant fight crime as vigilantes who pose as a notorious masked gangster and his aide.