The Southern Sun is a generation ship, or a spacefaring vessel that contains a large number of people, whose mission is to colonize a new world. Its voyage has lasted generations, so many of its inhabitants have been born and will die without ever setting foot on solid ground. This does not please the antagonist, Elijah Kalgan, who conspires with the pirates infesting the nearby Corona Borealis system and the ship’s Chief Engineer MacPhearson. Kalgan hatches a plot to disrupt the Southern Sun’s navigation systems and use the Enforcers, the ship’s police force, to hijack the ship and direct it towards this system. At this point, the inhabitants of the Southern Sun will have no choice but to accept his "generosity".
Kalgan sabotages a key part of the ship just as an important professor's shuttle is on a landing trajectory. The loss of guidance control causes the ship to explode. The shuttle's pilot, Dave Ryder, is able to escape, but the professor dies in the explosion. This sabotage seals off the flight deck for a number of weeks, which gives Kalgan the opportunity to attempt to wrest control. With the Enforcers in his hand, and with the flight deck out of commission, he holds the entire population of the Southern Sun hostage. Commander Jansen and Captain Devers enlist Ryder’s assistance, aided begrudgingly by Jansen’s daughter Dr. Lea Jansen, to regain control of the ship. . During this conflict a number of characters meet with untimely ends due to railing kills.
As Mike Nelson says in the DVD intro, "It's kinda hard to figure out what the 'mutiny' really is." In any case, we can be sure that many people fall over safety railings in the course of their deaths.
- A prominent member of the Southern Sun's bridge crew is killed during a bar scene in an apparent attempt to make the plot more interesting. However, she is in the next scene alive and well at her console on the bridge. No mention is made of any twins (though, to give the movie the benefit of the doubt, she's only briefly seen in the foreground and is not featured again after her death).
- The space-battle footage is all lifted from the TV series Battlestar Galactica (1978).  The SOL crew do not comment on this during the episode, but mention of it was made later on the MST3K section of the Sci-Fi Channel website. The BBI staff apparently did not recognize the footage as being recycled until after the episode aired.
- Two of Cameron Mitchell's children had bit parts in this movie. His son Chip played the thinly mustached Blake who apologizes for the "scanty" information. His daughter Cammile was the voice of the lead Bellerian, Jennera.
- Actor James Ryan, who is the object of several jabs by the SOL Crew for his rather well-done (yet vaguely psychotic) performance as one of the two villains, starred in many similarly low-budgeted South African productions like this.
- The other mutiny leader is played by John Phillip Law, who (like Robert Z'Dar and Joe Estevez) would be in more than one movie experiment during the show's final seasons. Law starred in Diabolik, the final episode/experiment.
- Reb Brown and Cisse Cameron are actually married in real-life and were already a wedded couple when Space Mutiny was filmed. Contrary to the SOL crew's jokes, Cameron is actually a few years younger than Brown.
- Cisse Cameron would later claim that Space Mutiny was intended to be a spoof of science fiction films.
- About Mike's understandable confusion regarding the mutiny, while Kalgan himself is obviously evil, sites such as TV.Tropes point out that all we really know about the other mutineers is they don't want to spend the rest of their lives on the ship. The only attempt the movie makes to portray this as wrong is a scene saying that leaving the ship before arriving at its predetermined destination would break "the law of the universe," but it then declines to provide any specifics.
- RiffTrax presented Space Mutiny live on June 14, 2018, complete with new jokes and new nicknames for David Ryder. (Flex Limpshaft, Burpee McCrossfit, Crash McPunchFace, Gunner Battlepants...)