The Mind of Evil

056 – The Mind of Evil
Doctor Who serial
The Doctor and Jo find themselves locked in a prison cell
Cast
Doctor Jon Pertwee (Third Doctor)
Companion Katy Manning (Jo Grant)
Others Nicholas Courtney — Brigadier Lethbridge-Stewart Richard Franklin — Captain Mike Yates John Levene — Sergeant Benton Roger Delgado — The Master Fernanda Marlowe — Corporal Bell Patrick Godfrey — Major Cosworth Simon Lack — Kettering Pik-Sen Lim — Chin Lee Kristopher Kum — Fu Peng Tommy Duggan — Senator Alcott Raymond Westwell — Prison Governor Michael Sheard — Dr Roland Summers Roy Purcell — Chief Prison Officer Powers Eric Mason — Senior Prison Officer Green Dave Carter, Bill Matthews, Barry Wade, Martin Gordon, Tony Jenkins — Prison Officers Clive Scott — Arthur Linwood Neil McCarthy — George Patrick Barnham William Marlowe — Mailer Hayden Jones — Vosper David Calderisi — Charlie Johnny Barrs — Fuller Matthew Walters — Main Gates Prisoner
Production
Directed by	Timothy Combe
Written by	Don Houghton
Script editor	Terrance Dicks
Produced by	Barry Letts
Executive producer(s)	None
Incidental music composer	Dudley Simpson
Production code	FFF
Series	Season 8
Length	6 episodes, 25 minutes each
Originally broadcast	30 January–6 March 1971
Chronology
← Preceded by Followed by → Terror of the Autons The Claws of Axos
List of Doctor Who serials

The Mind of Evil

Author	Terrance Dicks
Cover artist	Andrew Skilleter
Series	Doctor Who book: Target novelisations
Release number	96
Publisher	Target Books
Publication date	11 July 1985
ISBN

The Mind of Evil is the second serial of the eighth season of the British science fiction television series Doctor Who, which was first broadcast in six weekly parts from 30 January to 6 March 1971.

The Doctor and Jo visit Stangmoor Prison in England to witness a demonstration of the Keller Machine. This machine, invented by Emil Keller, a professor of criminology, extracts the negative (or evil) impulses from the minds of hardened criminals. But Keller is really the Master in disguise, and the so-called machine actually contains an alien mind parasite that feeds on, and can destroy, living minds. The Master is plotting to start World War III by destroying the World Peace Conference in London, using a nerve gas missile hijacked by the prisoners, and using the mind parasite (once it has fed sufficiently) to murder the American and Chinese delegates.

This serial was formerly lost from the BBC's television archive, the colour PAL videotapes on which it was made having been wiped in the 1970s. Only a monochrome telerecording, made on film for overseas sale of the programme, survived. But the serial has been restored using advanced computer technology to recolour one episode (by manually colouring key frames, then applying motion estimation to recolour the other 90%) and by extracting a colour signal - thought lost, but recorded by accident onto the monochrome film negatives - to restore colour to the other five episodes.

The Third Doctor and Jo Grant visit Stangmoor Prison to examine a new method of treating criminals, whereby negative impulses are removed from the mind using the Keller Machine. Professor Kettering, who is managing the use of the process at the behest of the absent Emile Keller, reconditions a number of inmates including Barnham, a hardened criminal who reverts to an innocent and childlike state due to the process. The Doctor’s suspicions about the Keller Machine are heightened following a string of deaths, including that of Kettering himself, which occur when the machine is operated. Each death seems to involve personal phobias – and the Doctor is threatened by an inferno when he gets too close to the machine.