Perhaps the modern trend of Doctor Who bookending its series with elements of an ongoing story arc can be traced back to The Key to Time. Although episodes in between have only small references to the Doctor’s quest and the Guardians, the first and last serials feature these things prominently, and The Armageddon Factor wraps it up for good. It is not the most thorough of resolutions – I’m still none the wiser as to who the Guardian was or why a Key to Time even existed in the first place – but there are a few good twists and some nice drama to this one in itself.
It’s a very “plotty” serial, for want of better term. A lot happens and everything intertwines. There’s a lot of really good science-fiction concepts too, such as a nuclear war between neighbouring planets, a computer controlling things behind the scenes, mind-control devices, a perpetual time loop and a mysterious figure pulling the strings.
We also meet an old friend of the Doctor’s, Drax, and suddenly the rather dark tone of the story changes for silly comedy (including a sequence involving a shrink ray). Curiously, Drax calls the Doctor “Theta Sigma” (presumably another nickname?) and suggests that “The Doctor” might just be a title he acquired after earning his doctorate. Although what’s perhaps more curious is that he recognises the Doctor by sight, even though his face has changed!
Drax is quite fun, but his persona is weirdly comedic in a story that is otherwise fairly grim. The Shadow is the main villain of the piece, the servant of the Black Guardian. With his wonky skull mask and sinister voice, I thought he was quite good. I also liked the twist reveal at the end, but it does leave things open for possible future stories. K-9 has a hard time in this one, almost getting melted for scrap and later being brainwashed by the Shadow, but he turns out alright.
In Romana, K-9 and the Doctor, we’ve had a Tardis full of smartypants for this series, but it’s actually worked out quite well. I see the appeal of having a human presence to keep the audience grounded, but this shows that it’s not always necessary, and Romana’s intelligence takes some of the egotistical edge off of the Doctor’s character. It’s a change from the lonely wanderer that the Doctor is in the modern series, as is the presence of old Time Lord friends and entities of power handing out quests for him to do.
With the navigator circuits randomised so the Guardian cannot follow, the Tardis disappears into new adventures.