From TARDIS Index File, the free Doctor Who reference.

Doctor Who and the Invisible Enemy
Series:	Doctor Who- Target Novelisation
Release Number:	36 (given to later editions)
Doctor:	Fourth Doctor
Companions:	Leela, K-9
Enemy:	The Swarm
Setting:	Titan Base, Bi-Al Foundation, 5000’s ?
Author:	Terrance Dicks
Publisher:	Target Books, W.H. Allen & Co
Publication:	March 1979
Format:	Hardcover and paperback editions, 110 Pages
ISBN:	ISBN 0-426-20054-3
Previous Story:	Doctor Who and the Horror of Fang Rock
Following Story:	Doctor Who and the Image of the Fendahl

Novelisation

• This novelisation is based on the original television serial (DW): The Invisible Enemy which was shown from 1st October 1977 and written by Bob Baker and Dave Martin
• The cover and information shown on the right is for the original Target novel and featured the artwork of Roy Knipe. (See below for information on other UK and international editions which published with a different cover).

Publisher's Cover Blurb

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 …

Illustrations

• None

Deviations from the Televised Story

To be added

Author, Writing and Publishing Notes

• To be added

Associated Images

To be added

Publishing History (UK)

To be added

First Publication:

• Hardback

W.H. Allen & Co. Ltd. UK

• Paperback

Target

Re-issues:

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

International Editions

To be added

External Sources

• The Target Book by David J Howe (Telos Publishing 2007)
• On Target a comprehensive guide to the Target novelisations by Tim Neal