Doctor Who: The Invisible Enemy (Story #93)

7.5 Overall Score
Story: 7/10
Acting: 7/10
Visuals: 7/10

Good episode, introduction of K-9

The Nucleus of the Swarm just looks like a prawn


Oh K-9…How I loathe you!

The Doctor (Tom Baker) and Leela (Louise Jameson) find the Doctor infected with a dangerous virus called the Nucleus of the Swarm.  As the Doctor fights the infection, Leela transports him to a space medical center for help.  Leela meets Professor Marius (Frederick Jaeger) and his robotic dog assistant K-9 (voiced by John Leeson) who work to save the Doctor before the infection spreads out of control.  As the infected agents of the Nucleus of Swarm seek their host in the Doctor, clones of the Doctor and Leela are sent inside of the Doctor’s body to stop the infection.

Doctor Who:  The Invisible Enemy aired in the fifteenth series of Doctor Who.  It was a four part serial airing from October 1, 1977 to October 20, 1977 and introduced K-9.  The series followed Doctor Who:  The Horror of Fang Rock and has been collected in The Tom Baker Years as Story #93.  Also included in the DVD collection is the one-shot series spin-off K-9 and Company:  A Girl’s Best Friend from 1981.


Hey Doctor…you’re complex inside and out

Doctor Who:  The Invisible Enemy was one of the better Doctor Who stories.  It falls under one of the “scary” Doctor Who stories with the infection of the Nucleus of the Swarm slowly taking over the space station then the medical center.  It goes into an almost Fantastic Voyage when the clones of Leela and the Doctor enter the Doctor’s body.  Obviously the special effects aren’t a high point in the episode but it still is an interesting concept.  Once the Nucleus of the Swarm is pulled from the Doctor, it is revealed to look like a shrimp…sorry but the scaley faced people were much more threatening than a prawn.


So let me get this straight…I had a shrimp inside of me?

The introduction of K-9 also is a big issue.  K-9 is kind of divisive.  It was very childish, had difficulties working and only could travel on smooth surfaces making it a tough companion for the Doctor.  I find K-9 kind of obnoxious and annoying and was fine with it leaving in the ’80s.  It is rather interesting to see him go rounds with someone like the Doctor but the banter with people like Leela (and later Sarah Jane) seems pointless since he is pretty much the Doctor in his discussions.  There is a fun kitschiness to K-9 that does embody the show, and I actually kind of enjoyed the K-9 and Company episode.

Doctor Who:  The Invisible Enemy is a must for fans of the series.  With the introduction of K-9, it marks an important episode for Doctor Who, and if you pick up the DVD the addition of K-9 and Company makes it even better.  Doctor Who:  The Invisible Enemy was followed by Doctor Who:  Image of the Fendahl.

Preceded By:

Doctor Who:  The Horror of Fang Rock (Story #92)

Followed By:

Doctor Who:  Image of the Fendahl (Story #94)

 Related Links:

K-9 and Company:  A Girl’s Best Friend

Author: JPRoscoe View all posts by
Follow me on Twitter/Instagram/Letterboxd @JPRoscoe76! Loves all things pop-culture especially if it has a bit of a counter-culture twist. Plays video games (basically from the start when a neighbor brought home an Atari 2600), comic loving (for almost 30 years), and a true critic of movies. Enjoys the art house but also isn't afraid to let in one or two popular movies at the same time.

Leave A Response