The way these serials kept people coming back to theaters to see them were by repetition and a steady stream of it. If you can appreciate the kitsch value and camp behind “Commander Cody” you could probably ignore the inherent repetitive storylines that follow it. Commander Cody is doing something top secret. There’s a villain who is spying on him. Commander Cody is also spying on them, oddly enough. The villain’s gun wielding henchmen take Commander Cody’s sidekick, the spunky Joan, hostage. Cody then has to go and save her, and wins the day. These serials deliver what the audience wants, even if it can get kind of tedious; especially since the compilation of “Sky Marshal of the Universe” episodes amount to almost four hundred minutes total.