The Great Secret

Mandrake and his team attempt to prevent "The Wasp" from stealing and using a new Radium invention.

Government agents work to interfere with schemes to trick the Comanches into war with the Texans.

Before the outbreak of WWII, Nazi sympathizers plot to undermine America.

A movie serial in 13 chapters: Some swampland becomes valuable, and various factions squabble over ownership of it.

Mystery and adventure, surrounding a stolen rubber harvest.

Jim Dorn endeavors to protect Jean McNain from a man she knows has committed a murder, Carter Snowden

Four flying G-Men protect America against enemy spies; one of the four assumes the identity of The Black Falcon, to befuddle the saboteurs even...

Pulp hero "The Spider" seeks to destroy all criminals. In this serialized adventure, he battles The Octopus, who intends to replace the government...

A bunch of waterfront youths pursue the Sea Raiders, a gang of saboteurs.

A reporter and a detective team up to solve the murder of a nightclub singer who had been involved in a divorce scandal.

This serial told the story of the diamond heir loom of the Stanley family.

Criminals steal a radium-powered tank from an inventor. His heiress and a government agent take up the chase. 18 episode serial-1. The Mystic Stone,...