The Armageddon Factor is the sixth and final serial of the 16th season of the British science fiction television series Doctor Who, which was first broadcast in six weekly parts on BBC1 from 20 January to 24 February 1979.
Soon after, while searching for the Key to Time's final segment, the Fourth Doctor and Romana arrive, encountering Astra before she is suddenly abducted.
After some initial false accusations from the leading bull-headed military Marshal, the Doctor agrees to help his increasingly weak efforts against Zeos.
The Doctor is abducted during an attempt to transmaterialise/transmat (teleport) to Zeos, and meets with the true opponent, the "Shadow", ruling over a space station called the "Planet of Evil".
They return to Zeos, and, with the false Key segment and the time loop both expired, narrowly deactivate Mentalis' self-destruct, but the Doctor also realises that the Marshal is still en route.
The White Guardian appears on the TARDIS scanner screen to congratulate the Doctor on finding and assembling the Key to Time, and requests that it be sent to him.
[1] The villainous character of the crazed militarist, the Marshal of Atrios, with his endless calls for victory no matter what the cost in human life, was based upon Winston Churchill.
[1] During the course of rewrites, the character of Renia was renamed Astra, was made a princess instead of a scientist, and was given a more prominent role in the plot as compared to the original version.
[1] In his 1960 book On Thermonuclear War, the American futurist Herman Kahn wrote of a hypothetical Doomsday Machine, which he described as a computer controlling a stockpile of hydrogen bombs powerful enough to destroy all life on Earth that would be set off at the first sign of any nuclear attack from another nation or if there was an attempt to disarm it.
[1] The outgoing script editor Anthony Read rewrote the character of Drax to make him into a bumbling Cockney comic sidekick who was portrayed as the "lovable rogue" archetype commonly associated with British criminals.
[1] Williams had wanted to fire Baker during the production of The Armageddon Factor, arguing that he played the Doctor for too long and he found him a difficult actor to work with.
[1] The BBC executives were able to negotiate a truce between Williams and Baker who both agreed to return for another season, but relations between the star and the producer remained tense.
[10] Paul Cornell, Martin Day, and Keith Topping gave the serial an unfavourable review in The Discontinuity Guide (1995), describing it as "a dreary end-of-season Oh-my-God-the-money's-run-out 'spectacular'" without subtle acting.
[12] In The Television Companion (1998), David J. Howe and Stephen James Walker wrote that The Armageddon Factor was "entertaining enough in itself, with some good direction by Michael Hayes and generally fine production values, but ultimately fails to tie up all the loose ends and leaves the over-arching plot strangely unresolved".
[3] On the other hand, DVD Talk's Justin Felix gave the serial four out of five stars, saying that it "packs more of a wallop than the previous two stories" and had everything typical of Doctor Who.
[2] Booker noted that there was a contradiction between the serial's anti-war message along with its depiction of villains such as the Shadow who proudly self-identify as evil and who need to be resisted at all costs to allow good to prevail.
Along with the rest of season sixteen, it was released on DVD in North America as part of the Key to Time box set in 2002, only available in Region 1.