In 1936 Republic made a very boring serial called Undersea Kingdom. But it had some fancy aircraft effects. In 1941 Republic made an okay serial called The Adventures of Captain Marvel. But it had amazing flying footage of Marvel. In 1949 Republic made a reasonably good serial called King Of The Rocketmen. More amazing flying effects. This was all a lead up to something. In 1952 Republic would make a true comic book classic.
Republic Studio effects man Mr Howard Lydecker is the most under-rated effects man in Hollywood. His work in Radar Men (and the above mentioned serials) steals the show. We have full scale spaceships, miniature spaceships, rocketman flying in the sky, fancy sci-fi hardware all over the place (including an early model of that female robot from the Lost In Space episode "Ghost Planet"), it is all here!
I also like looking at 1950s cars race around country roads and there is no shortage of that here. All great stuff! The cast? I don't know any of them but who cares? This is just screen comic book entertainment and nothing else. In the 1960s Howard Lydecker would do effects for TV's Lost In Space and Voyage to the Bottom of the Sea.