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Doctor Who and the Invisible Enemy was a novelisation based on the 1977 television serial The Invisible Enemy.

Publisher's summary[]

A mysterious cloud drifts menacingly through space...

A sudden energy flash and the Doctor is infected with the Nucleus of a malignant Virus that threatens to destroy his mind.

Meanwhile, on Titan, human slaves prepare the Hive from which the Virus will swarm out and infect the universe.

In search of a cure, Leela takes the Doctor to the Foundation where they make an incredible journey into the Doctor's brain in an attempt to destroy the Nucleus.

But can the Doctor free himself from the Nucleus in time to reach Titan and destroy the Hive? Luckily he has help – in the strangely dog-like shape of a mobile computer called K9 ...

Chapter titles[]

  1. Contact
  2. The Host
  3. Death Sentence
  4. Foundation
  5. Counter-Attack
  6. The Clones
  7. Mind Hunt
  8. Interface
  9. Nucleus
  10. The Antidote
  11. The Hive
  12. Inferno

Deviations from televised story[]

  • What happens to the antibodies is expanded upon.
  • Leela can fly the TARDIS despite not having seen the white console room before.
  • A deleted scene where the Nucleus tries to reinfect the Doctor to no avail is reinstated.
  • Leela's knife hits Meeker in the chest rather than the back.
  • The Doctor feigns unconsciousness before trying to shoot Leela instead of hiding around the corner.
  • There are scenes onboard the Bi-Al Foundation supply shuttle, showing the crew being infected before crashing into the asteroid.
  • In the budget-free constraints of the novelisation, Lowe infects more of the hospital personnel than is seen on-screen and has a small army during his second assault on the isolation room, rather than simply himself and three others as in the televised version.
  • The nurses are described as wearing robes, rather than the tight-fitting trouser suits seen on-screen.
  • It is mentioned that Professor Marius taught at New Heidelberg University.

Additional cover images[]

Writing and publishing notes[]

This was originally to be reprinted in spring 1994, along with Doctor Who and the Horror of Fang Rock. The cover art would have been by Alister Pearson.

British publication history[]

First publication:

  • Hardback
W.H. Allen & Co. Ltd. UK
  • Paperback


Scheduled for a new edition in July 1994, but the release was cancelled.


This Target Book was released as an audiobook on 2 August 2018 complete and unabridged by BBC Audio and read by John Leeson.

The cover blurb and thumbnail illustrations were retained in the accompanying booklet with sleevenotes by David J. Howe. Music and sound effects by Simon Power.

External links[]