For other uses of The Mysterons see The Mysterons (Disambiguation).
The Mysterons is 1st produced episode and the 1st broadcast episode of the series Captain Scarlet And The Mysterons.
In the year 2068, the Spectrum organization sends Captain Black and two others in the Zero-X to Mars, where they discover a mysterious alien city inhabited by beings known as the Mysterons. At first, the Mysterons are friendly and curious, and gaze at the Earthlings through a strange scanner; unfortunately, the humans mistake the equipment for a weapon; firing upon the city, and destroying it completely. A strange ray envelops the city, which then proceeds to rebuild itself. The Mysterons, enraged by the earthmen's actions, wage a "War of Nerves" against the Earth, turning Captain Black into their main agent of destruction, unbeknown to Spectrum.
Meanwhile, Spectrum has discovered the Mysteron's plans, and their threat to kill the World President. Colonel White sends two of his best agents, Captain Scarlet and Captain Brown, to protect the President. On the way, they are killed by the Mysterons and retrometabolised into perfect clones.
After the retrometabolised version of Captain Brown has failed (by exploding his body in an underground room), the retrometabolised clone of Captain Scarlet (at that point believed by Spectrum to be the original), kidnaps the President. He takes him to the roof of an immense car-park, where the Mysterons have arranged for an aerial attack by helicopter. However. due to a bizarre twist of fate, Scarlet, injured, falls from the Car-Vu, is pronounced dead, but then revives.
Found to be free of Mysteron mind control, Scarlet regains his original personality, but now has the unique ability to regenerate from any fatal wound, hence rendering him indestructible, and qualifying him as Spectrum's number one agent and a sworn enemy of the Mysterons.
- Harmony Angel was voiced by Liz Morgan in this episode, she was voiced by Lian Shin in all other appearances.
- When inside the Spectrum Passenger Jet, Captain Scarlet and the World President are both wearing pilot glasses. However, some exterior shots show them without them.