American, British and Chinese secret agents battle the Japanese Black Dragon Society, a secretive ring that smuggles enemy agents into the U.S. disguised as mummies.

Alan Armstrong, aka Spy Smasher, battles a Nazi villain known as The Mask, who heads a gang of saboteurs determined to spread destruction across America.

The chapter-crunched version of this 196 minutes, 12-episode serial from Republic finds Canada being bombed mercilessly by a mysterious-enemy plane (shaped like a boomerang) called the Falcon, under the supervision of Admiral Yamata, Count Baroni and Marshal von Horst, chiefs of the Axis Fifth Column in Canada. No one can identify the plane until American inventor, Professor Marshall Brent, and his daughter Carol arrive with a new type of airplane detector. This poses a threat to the Axis chiefs in preparing western Canada for an invasion and they have him kidnapped by local Quisling Gil Harper. RCMP Sergeant Tom King attempts to rescue Brent, but the inventor is killed when a plane in which he is held captive crashes into a riverboat. Carol, determined to carry on her father's work and with King's aid, manages to prevent the enemy agents from capturing the detector, and destroys the device (many chapters later) when the agents make a last desperate attack on the cabin where it is hidden. She is captured and taken to the crater of a volcano, where the ring makes its headquarters.

Mountie sergeant and his three constables find themselves facing multiple perils at the hands of an outlaw gang which, aided by a corrupt Indian medicine man and his followers, have brought a halt to construction of a key railroad line through the Canadian Northwest.

Reporter Brenda Starr (Joan Woodbury) and her photographer Chuck Allen (Syd Saylor) get involved in a search for the loot from a payroll robbery. Cliffhanging action and adventure and a fair amount of comic relief follow them at every turn.

It's intrepid Nyoka and her friends versus Vultura, Queen of the Desert, on a quest for the Golden Tablets of Hippocrates.

An American secret agent travels to Africa to infiltrate a Nazi spy ring.

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

A 20th Century pilot named Buck Rogers and his young friend Buddy Wade awake from 500 years in suspended animation to find that the world has been taken over by the outlaw army of Killer Kane.

Filmed in the Sierra Nevada mountains near Sonora, California, this Universal serial is Universal's 40th sound-era serial. Eagle Scout Bruce Scott, leader of Martinsville Troop Number One, and his pack sets off in search of lost treasure and finds adventure.

A famous detective sets out to discover who stole $2 million in bonds.

A young radio cop and a beautiful girl try to stop an international criminal gang from getting their hands on the formula for a new bulletproof steel.