Similar to the earlier patch job known as "Crash of Moons", Space Ranger Rocky Jones (Richard Crane) assembles his gang here once again to avert a threat to Earth, though not as ominous as the one in the earlier film. Most of the action as it were, takes place on Fornax, a moon of Jupiter. The mystery of the film seems to be how Professor Newton (Maurice Cass) believes that the environment on Fornax might be hostile to humans, when eight years earlier an Earth rogue named Cardos exiled himself to the moon to escape his criminal past. There he's been ingratiating himself with Zoravac (Walter Coy), the ruler of Fornax.
What gives the film some of it's dubious fun is the extensive use of pseudo scientific jargon. Making a return appearance are the viseograph and the astrophone, but perhaps most impressive was the mechanical canary used to test the atmosphere on Fornax; too bad they didn't come up with a more colorful handle for it.
This time around, Rocky's young ward Bobby (Robert Lyden) is given a playmate, the daughter of Zoravac named Volaca. As expected, the pair wind up in places they don't belong, but manage to help Rocky and Winky (Scotty Beckett) save the day and the millennium. Once again, Winky has the film's most memorable line - "Well rattle my rocket reflexes".
Though uncredited in the film, bad guy Cardos is portrayed by Nestor Paiva. You might recognize him as the Amazon boat captain Lucas from a couple of the "Creature of the Black Lagoon" movies.
Like it's predecessor "Crash of Moons", this film is a fun diversion, even if just to get a view of how far we've come in both space technology and film making. I got a bit of a chuckle out of the mention of an interplanetary agency called the 'Office of Space Affairs'. Had it still been around for the launch of the Star Ship Enterprise, they might have been kept real busy investigating Captain Kirk.
Review by classicsoncall from the Internet Movie Database.