Doctor Who has long been my favorite show, but until recently rewatchings of old episodes have been few and far between. This has changed in the last couple of years as I have been using birthday and Christmas money to buy some of the old episodes, usually enjoying them with one or two of my nerdier daughters. This year, though, my wife and I bought a year of Britbox for each other as a gift, which gives me access to nearly all of classic Who.
The Invisible Enemy
Starring Tom Baker as the Fourth Doctor
Companions: Louise Jameson as Leela and John Leeson as the voice of K9.
Written by Bob Baker and Dave Martin. Directed by Derrick Goodwin. Produced by Graham Williams Script Edited by Robert Holmes.
Format: 4 episodes, each about 25 minutes long
Originally Aired: October 1977 (Episodes 5-8 of Season 15).
The Invisible Enemy is a story I have long-thought of being kind of silly, even by standard of old Doctor Who. It comes after a long run of generally good stories (which I last commented on here) and possibly reflects the change in tone brought on by the show’s newish producer, Graham Williams…although I’m just speculating here. What’s notable about the story is the introduction of K9, the show’s popular and long-running robotic companion.
Spoilers Ahead!
The Invisible Enemy starts off decently enough, with an alien threat invading humanity in the form of an intelligent virus. This threat easily spreads from host to host, with each infected person becoming part of its collective intelligence–a little bit like Star Trek’s Borg, but with less convincing effects. Adding to the tension is the fact that the Doctor himself is infected by the so-called Nucleus, the apparent heart of this attack. It’s later revealed that the virus attacks intelligence, so it’s natural that it was drawn to the Doctor. Leela, by way of contrast, is a creature of instinct, and is therefore immune. (Unilke poor Jamie from The Krotons, she’s not described as stupid).
The ever-reliable Michael Sheard is the main guest star of the first episode, but his role ends up being an unrewarding one, as Supervisor Lowe does not last long before getting infected, and then is just another mindless drone serving the Swarm. Up until this point the story is a decent little cat-and-mouse thriller, with Leela trying to make sense of what is happening and the Doctor struggling to keep ahold of himself.
Once the story gets us to the Bi-al Foundation, it takes a strong left-turn into crazyville.
You’ve got Frederick Jaeger and his nutty accent, you’ve got K9 the robot dog, and you’ve got the Doctor cloning himself and Leela and sending them on a suicide mission inside his own head! Everyone seems to accept this like it’s a Sunday picnic in the park. The clones seem perfectly happy with their pre-ordained fate, and it’s even the fact that the cloned Leela’s antibodies got re-absorbed by the Doctor after she died which saves him from the virus. It definitely seems like there’s a moral quandary getting glossed over there.
And of course there’s the Nucleus–a big special effect puppet that Tom Baker apparently found it hard to act against because it looked too much like a prawn. This is a classic example of Doctor Who punching above its weight-class as far as special effects are concerned, which is something that the show did regularly. We always have to activate a lot of suspension of disbelief with this show, but in these sequences in this story we have to set it at overdrive.
More successful are the story’s model shots. The spaceship landing at Titan base, and the story’s big explosions–all of that looks pretty good.
Unfortunately, regardless of how successful the effects are or are not, The Invisible Enemy is lacking anything to hang your hat on from a character or dialogue point of view. Marius is extreme to the point of semi-cartoonishness, whilst the rest of the humans are all dull and one-note. And there’s not even much between the Doctor and Leela to keep us engaged, especially once they reach the medical station. All of the attention is taken up with the varied (but not fully-developed) ideas, or the (not really successful) action storyline. Even there, Leela spends a lot of her time standing behind K9 while he shoots things. In the midst of all this the personalities on screen become a bit flat. I feel like this is a regular weakness in the work of Bob Baker & Dave Martin, although I haven’t rewatched all their stories yet, so I may be wrong.
Certainly when you look at the writers on the surrounding stories–Robert Holmes, Chris Boucher, or Terrance Dicks for example–this adventure compares pretty unfavorably. Having just rewatched The Face of Evil, it’s pretty disappointing to watch the Doctor and Leela be so undynamic with each other.
Ultimately, the most interesting thing that happens in The Invisible Enemy is what I’ve already mentioned–K9 is introduced.
I can see that working with the K9 prop might have been annoying but the little robot dog immediately makes a good impression, and in the post-Star Wars and R2-D2 world that this story was developed in, it’s no surprise the decision was made to add him to the regular cast (even if it’s pretty conspicuous that he always has to go through the TARDIS doors off-camera.) I’m not even the biggest fan of the artificial intelligence, but he’s a lively presence in the show and John Leeson does memorable work voicing him.
One little detail to mention about the design work of the story (by Barry Newbery)–there are a lot of written signs around both of the major settings of the story, and all of them are written with both a funny spelling and a funny font. The spelling is semi-phonetic, so “Egsit” instead of “Exit”, and the font has all the letters coming out of these solid blocks which sit on top of every letter. It’s obviously an attempt to make it all look “space-age,” but like most such efforts it ends up just being peculiar.
In the end, the heavy lifting of The Invisible Enemy is left to it’s broad range of imaginative story ideas. It carries these off in a way that never really engages emotionally or even intellectually (in spite of some efforts to do so with talk about the Nucleus’ right to survival), so the whole thing feels a bit shallow. It is not, however, boring, which puts it a step above some stories I’ve seen recently, including Revenge of the Cybermen.
And it’s got K9 in it in a pretty sizable role (he gets to shoot infected people a lot), which mixes up the dynamic in a fun way.
Blue Towel Productions 
The chemistry between Tom and Louise was sadly never quite the same after Horror Of Fang Rock. And K-9 didn’t get the best to shine until The Key To Time. It was clearly that after Hinchcliffe’s era it would become much harder to recapture the best magic for the classic Doctor Who. Thanks, Ben, for your review.