Captain Scarlet and the Mysterons

A manned expedition led by Captain Black of Spectrum lands on Mars; investigating the planet surface in an exploration vehicle, the crew discover a futuristic alien city.

The Mysterons threaten the life of the Director General of the United Asian Republic and Spectrum swings into action to protect him as he prepares to board his private plane at London Airport.

The Mysterons threaten to destroy London and a truck carrying an atomic device goes missing in the city. The only clue to its whereabouts is the truck driver, found unconscious in the street

The Mysterons make their first mistake when Captain Black, revealed to have become a Mysteron agent, breaks into the Culver Atomic Centre and is exposed to radioactivity that will enable Spectrum to track him with directional geiger counters.

The Mysterons threaten to destroy key links in the Frost Line Outer Space Defence System.

The Mysterons threaten to kill Colonel White and after their initial attempt fails, White elects to leave Cloudbase so as not to place the other Spectrum agents in jeopardy.