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Episode Guide
Production Code: 5V
Season 18, Story Number 116
Directed by Peter Grimwade

Each episode is identified with date of transmission, duration, ratings in millions, and (for 1963-1974 only) archive status.

Part One
28 February 1981 | 24'32" | 7.1
Part Two
07 March 1981 | 24'03" | 7.7
Part Three
14 March 1981 | 24'32" | 5.8
Part Four
21 March 1981 | 25'10" | 6.1
Archive Status: All four episodes exist as PAL 2” colour videotape, always held by the BBC’s Film and Videotape Library.
Tom Baker (Doctor Who), Matthew Waterhouse (Adric), Sarah Sutton (Nyssa), Janet Fielding (Tegan Jovanka), Anthony Ainley (The Master), Dolore Whiteman (Aunt Vanessa), John Fraser (The Monitor), Tom Georgeson (Detective Inspector), Christopher Hurst (Security Guard), Peter Davison (The Doctor)
With his ship's Cloister Bell tolling of impending doom, the Doctor decides to repair the TARDIS's chameleon circuit and so goes to Earth to obtain the exact external dimensions of a real police box which can be used correctly to reconfigure the ship. While he is there, an air hostess, Tegan Jovanka, en route to her new job, enters the TARDIS thinking it to be a real police box.

The Master has devised a complex trap for the Doctor and kills Tegan's aunt Vanessa. The Doctor is apparently warned of an impending ordeal by a mysterious figure in white, the Watcher, who appears to him several times. The Doctor goes to Logopolis, a planet of mathematicians, but the Master in his TARDIS has hitched a ride in the Doctor's TARDIS and now starts killing the Logopolitans. The Watcher appears again, having brought Nyssa from Traken to Logopolis.

The Master's meddling causes the Logopolitans' complex block transfer computations to go wrong, culminating in his use of a sound suppressor to prevent the calculations from being spoken at all - the means by which the Logopolitans run their programs.

The Monitor on Logopolis explains that it is his people's calculations that are keeping the universe from destruction. It passed its normal heat death years ago, and the Logopolitans' programs are holding open numerous CVEs through which the excess entropy from our universe is draining. With the Master's interference, the CVEs will close and the Universe will be destroyed. Watching on the TARDIS scanner, Nyssa sees Traken destroyed as the entropy begins to take effect.

The Doctor and the Master join forces to prevent the destruction of the universe and hurry to the Pharos Project in Cambridge on Earth with a copy of the Logopolitan program. They intend to use a radio telescope to transmit it and thus keep the CVEs open. The Master sees an opportunity to seize power and promptly blackmails the peoples of the Universe with destruction unless they agree to his demands. The Doctor tries to prevent the Master from carrying out his threat and succeeds, only to fall from the gantry of the radio telescope.

As he lies under the telescope, Adric, Nyssa and Tegan rush to join him. The Watcher appears once more and merges with the Doctor as he regenerates into a younger form.

Synopsis from Doctor Who: The Fourth Doctor Handbook by David J. Howe, Mark Stammers and Stephen James Walker, reprinted with permission; further reproduction is not permitted.

Production Team
Val McCrimmon (Assistant Floor Manager), June Hudson (Costumes), Malcolm Thornton (Designer), Barry Letts (Executive Producer), Peter Hall (Film Cameraman), Paul Humfress (Film Editor), Paddy Kingsland (Incidental Music), Dorka Nieradzik (Make-Up), John Nathan-Turner (Producer), Angela Smith (Production Associate), Margot Heyhoe (Production Manager), Christopher H. Bidmead (Script Editor), Dick Mills (Special Sounds), Henry Barber (Studio Lighting), John Holmes (Studio Sound), Peter Howell (Theme Arrangement), Ron Grainer (Title Music), John Horton (Visual Effects)
Story Notes
The final story of the fourth Doctor, "Logopolis" bid farewell to Tom Baker as he plummeted to his doom from the Pharos Project radio telescope, affording companions Adric and Nyssa and new friend Tegan Jovanka (introduced in this story as played by actress Janet Fielding) the ability to say goodbye as he regenerated. The lead up to the Doctor's regeneration at the conclusion of Logopolis included two compilations of clips featuring old enemies and friends of the Doctor. The enemies were the Master (The Deadly Assassin part one), a Dalek (Destiny of the Daleks episode four), the Pirate Captain (The Pirate Planet part four), a Cyberman (Revenge of the Cybermen part three), Davros (Genesis of the Daleks part five), a Sontaran (The Invasion of Time part five), a Zygon (Terror of the Zygons part three) and the Black Guardian (The Armageddon Factor part six). The companions were Sarah (Terror of the Zygons part two), Harry (The Sontaran Experiment part two), the Brigadier (Invasion of the Dinosaurs part two), Leela (The Robots of Death part one), K-9 (The Armageddon Factor part two), Romana 1 (The Stones of Blood part one) and Romana 2 (Full Circle part one). The sequence was repeated with different music and overdubs as a pre-title sequence before the first Peter Davison story "Castrovalva." The Watcher was played by actor Adrian Gibbs, who was not credited in the Radio Times or on screen. It was decided only late in the day that Nyssa would be a continuing character, so the other new companion, Tegan, was actually cast first; Nyssa does not appear until Part Two and is not credited on Part One. The Master, although credited on Parts One and Two, is not seen until Part Three; only his chuckle is heard in the earlier episodes. Barry Letts departed at the end of this year as executive producer, as did Christopher Bidmead as script editor (though Bidmead wrote the stories "Castrovalva" and "Frontios" for the Fifth Doctor). Tom Baker's involvement with Doctor Who after his departure consists primarily of a guest shot in the "Dimensions in Time" special as well as his narration of the "Shada" and "The Tom Baker Years" documentaries.
For more in-depth information about the contents of this story, a complete episode-by-episode detailed breakdown can be found at the Doctor Who Reference Guide.
Additional, more detailed information about the production of this story can be found at Shannon Patrick Sullivan's A Brief History of Time (Travel).
DVD release
Due for DVD release as part of "The Return of the Master Boxed Set" in January 2007 in the UK; US/Canada and Australia/New Zealand release dates and DVD details unknown. Boxed set will include "The Keeper of Traken," "Logopolis" and "Castrovalva"
Video release
Released as “Logopolis” in the UK [March 1992] and Australia/New Zealand [September 1992] (BBC catalog #4736), US/Canada [October 1993] (WHV catalog #E1142); episodic format, cover illustration by Andrew Skilleter.
In Print
Novelised as “Doctor Who – Logopolis” by Christopher H. Bidmead (Target #41), first released in 1982 with cover art by Andrew Skilleter. Re-released in 1991 with cover art by Alister Pearson. Released in hardcover in 1982. Included as part of the “Fourth Doctor Who Gift Set” released in 1983.
For more details on the various novelizations of this story, with additional background material, artwork and details of both UK and foreign releases, visit On Target.
Screencap Descriptions
Descriptions of each story screen capture above right, top to bottom:
  • Tegan Jovanka (Janet Fielding) faces new adventure in the TARDIS
  • Logopolis, with its replica tower of Earths Pharos Project
  • the Master (Anthony Ainley) tricks Nyssa (Sarah Sutton) into believing hes still her father, Tremas
  • Adric (Matthew Waterhouse) helps the Doctor (Tom Baker) work on the measurements
  • the Logopolitans headed by Monitor (John Fraser)
  • the Watcher (Adrian Gibbs) keeps tabs on the Doctor
  • the shrunken bodies of the police constable and Tegans aunt
  • the Doctor attempts to stop the Masters fatal broadcast
  • the regenerated Fifth Doctor (Peter Davison)