Feature version of the 1938 film serial FLASH GORDON'S TRIP TO MARS. Flash Gordon fights Ming the Merciless once again to ensure the survival of the Earth.

Retired lawman Kentucky Wade and his three buddies, Mike Morales, "Dude" Hanford and "Trigger" Benton come to Brimstone and help their friends Larry Munro and his sister, Lucy , in their fight to retain control of Larry's rich ore mine. "Doc" Hardy , as an old friend of Wade's, joins them in their efforts to keep Matt Keeler , the scheming owner of "The Brimstone News", from his efforts to wrest control of Munro's property and mine. Keller employs a legion of henchmen, and sidelines at running runs guns to Red Hatchet and his tribe so they can also get in on the fray against the Munro's and Kentucky and friends.

Corporal Larry Grant and Sergeant "Mac" McGowan, of the United States Marine Corps, are rival for the love of Frances Schiller, but team up to hunt down "The Tiger Shark," a mad, scientific wizard who is holding Sergeant William Schiller, Frances' brother, a prisoner on a wild, jungle island in the Pacific.

A heavy condensation of the 1936 serial Flash Gordon, with altered musical score. Flash Gordon, Dale Arden and Dr. Hans Zarkov visit the planet Mongo to thwart the evil schemes of Emperor Ming the Merciless, who has set his planet on a collision course with Earth. Released abroad as "Flash Gordon" for countries not interested in booking the serial, and never shown in the USA before 1950, where the title was changed to "Rocket Ship".

A secret agent goes after the gang that stole the crown jewels of a European monarchy.

When a deadly Nitron ray strikes Earth, Flash Gordon and his friends travel to Mars to battle Ming the Merciless and his new ally Queen Azura.

Edited version of the 1939 Universal serial "Buck Rogers." 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.