28th February – 21st March 1981

It’s the end … but the moment has been prepared for.

The Doctor to his companions, episode 4

Tom as the Doctor with Anthony Ainley as the regenerated Master. Picture © BBC

When air stewardess Tegan Jovanka (Janet Fielding) and her aunt (Dolore Whiteman) break down on the Barnet by-pass, they are unaware that the police box nearby is the Master’s TARDIS. Its revived occupant (see The Keeper of Traken synopsis) is planning his greatest act of villainy; disrupting the work of Logopolis, a planet whose people’s skill in computer modelling events in the Universe, repairing them, and then beaming them back into space as replacement realities, is holding back the inevitable dissolution of the Universe. If this work is even paused, the ensuing cosmic destruction will be so great the Master will be able to blackmail whole space empires into handing power over to him.

Having scanned the Doctor’s mind while on Traken, the Master knows he intends going to Logopolis to undertake repairs to his TARDIS, after first landing on Earth to obtain accurate measurements of a real police box. The Master’s disguised ship enables him to ‘hitch a ride’ to Logopolis, but with an unplanned extra passenger, Tegan.

Once on Logopolis the Doctor and Adric are reunited with Nyssa, who has been brought here by a wraith-like being, identified only as the Watcher (Adrian Gibbs), whom the Doctor seems to know. Nyssa is searching for her father, Tremas, who has vanished from Traken. She spies a man who looks like a younger version of him, but it is the Master, already at work killing Logopolitans, thereby corrupting their monumental programming operations.

Even as the Doctor frantically convinces the Master that his scheme will have consequences no-one can control, a black void in the Universe opens and begins swallowing whole galaxies – even Nyssa’s home planet, Traken. Logopolis is faltering and even though its controlling programmer, the Monitor (John Fraser), is able to compute a patching program to contain the void, their system for implementing it has been destroyed by the Master’s actions.

Frantically the Doctor leads Nyssa, Tegan, Adric and the Master to present-day Cambridge where he knows of a deep space radio telescope that can be modified to transmit the fix programme. But the Master double-crosses him, introducing a jamming signal to halt the transmission, while he issues his own ultimatum to the powers that rule the Universe.

Resigned to a destiny revealed to him earlier by the Watcher, the Doctor climbs out onto the giant telescope’s frame and dives onto the cable powering the Master’s jamming signal. The fix program successfully transmits and the Universe is stabilised once more. The Master escapes but the Doctor is not so lucky, losing his grip on the cable and falling hundreds of feet to the ground.

It seems to be the end for the fatally injured Doctor until the ghostly Watcher – in truth an incomplete version of the Doctor’s future self – merges with him. The healing process of regeneration starts, and before the eyes of his three young friends, a new face framed by straight, blond hair appears; the face of the fifth Doctor…

Video © BBC

Logopolis is available on Region 2 DVD

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Logopolis is available on Region 1 DVD

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Logopolis is available on Region 1 DVD

as an individual release. To find out more click on the cover.

Logopolis is available on UK Blu-ray boxset

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Logopolis is available on North American Blu-ray boxset

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