Martian Menace (comic story)

Cardell conducts final tests on a Viper engine intended for an Angel aircraft from Workshop Four beneath the Arizona Desert.
Scarlet uses an electrode gun to kill the Mysteron Cardell.
White contemplates suicide "for the sake of Spectrum and the world" when confronted with three armed men he believes to be Mysterons.
Agents from the Universal Secret Service and the World Intelligence Network are rushed to Unity City upon hearing the news that the World President has disappeared.
President Younger accuses Whitway of mutiny and promises to have him court martialled for his actions. Whitway instead believes that he will be hailed as a hero and "the conqueror of the Mysterons" when he returns.
The Mysteronisation of Whitway and his troops is counted by TV 21 as the Mysterons' biggest victory since their assassination of Bereznik's President.
Scarlet and Ochre use an MEV to navigate the Frazer Gorge and the Rock Snake Mountains.
The Rock Snakes were the "original inhabitants" of Mars.

Story notes

Like most of TV Century 21's comic stories from the same period, this comic serial was not given a title in the pages of TV Century 21 during its original printing; the title instead comes from later reference sources.
As well as being a crossover with the Doctor Who universe, this story was also a crossover with Fireball XL5 through the Space Patrol craft Captains Scarlet and Ochre use to reach Mars and with Thunderbirds through the appearance of the Rock Snake which attacks them once they get there.

After General Whitway announces his intention to deal with the Mysteron threat to Kahra by attacking the Mysteron City, Colonel White decries the plan as "madness" and asks him to remember what happened to Captain Black. (COMIC: SPECTRUM, Traitor Black Gives In!, PROSE: Rogues Gallery et al.)