Holt of the Secret Service

A master thief coincidentally is robbing a house where a murder—in which the President of the United States is involved—occurs in front of his eyes. He is forced to run, while holding evidence that could convict the President.

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

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.

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.

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.

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

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.

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.

When his boss is killed, Detroit cop Axel Foley finds evidence that the murderer had ties to a California amusement park called Wonder World. Returning to sunny Beverly Hills once more, Foley reunites with Detective Billy Rosewood to solve the case. Along with Billy's new partner, Detective Jon Flint, they discover that Wonder World is being used as a front for a massive counterfeiting ring.

The villain of this serial, the "Wolf Devil", who's head covering amazingly looks to be a REAL wolf's head, is determined to eradicate the non native races from Alaska.