Doctor Who The Armageddon Factor Part 1

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. It was the last to feature Mary Tamm as Romana.

The serial is set on the planets Atrios and Zeos, and another planet in between them. In the serial, a nuclear war between Atrios and Zeos is nearing its end, but with Atrios losing. At the same time, the Shadow (William Squire), a henchman of the Black Guardian (Valentine Dyall), steals the time and space vessel the TARDIS, which contains the first five segments of the powerful Key to Time, and kidnaps Princess Astra of Atrios (Lalla Ward), who is the sixth and final segment.