Produced by the New York office of the series' distributor, ITC Entertainment, the film is a compilation of the Captain Scarlet episodes "The Mysterons", "Winged Assassin", "Seek and Destroy" and "Attack on Cloudbase".

Set in 2068, the original series depicts a "war of nerves" between Earth and the Mysterons: a race of Martians with the power to create functioning copies of destroyed people or objects and use them to carry out acts of aggression against humanity.

Earth is defended by a military organisation called Spectrum, whose top agent, Captain Scarlet, was killed by the Mysterons and replaced by a reconstruction that subsequently broke free of their control.

[2] Created by the New York office of ITC Entertainment, Captain Scarlet vs. the Mysterons was one of several TV film re-workings of Anderson series designed to renew overseas interest in these productions and promote syndication sales in the United States.

After the destruction of Cloudbase (as seen in the original TV episode), the Mysterons reverse time and restore the base while stating their intention to spare humanity; the voice-over is accompanied by a shot of a computer-animated pyramid.

[5] Noting that the last episode of the original Captain Scarlet ("The Inquisition") did not provide a resolution to the conflict between Earth and Mars, John Peel suggests that the material from "Attack on Cloudbase" was changed to give the series storyline a more satisfactory conclusion.