Serial DD:
The Tenth Planet


The TARDIS lands near an international tracking station in Antarctica. The year is 1986, and the Doctor, Polly and Ben are just in time to witness the arrival in the solar system of Mondas, a planet which is the mirror image of Earth. Soon, Mondas' natives, the Cybermen -- humans who have replaced much of their living tissue with cybernetic attachments -- invade the tracking station, as Mondas begins to drain the Earth of its energy. The time travellers must stop the process before the Cybermen begin to convert all humanity into creatures like themselves... but something is very wrong with the Doctor.


Kit Pedler had begun acting as Doctor Who's scientific advisor with The War Machines partway through the series' third recording block in early 1966. Later that spring, Pedler proposed a new idea to story editor Gerry Davis about a space capsule which had been drained of energy, the culprits being “star monks” who came from Earth's heretofore unknown twin planet. (Davis has indicated the “twin planet” idea was his suggestion.)

Although he liked Pedler's general concept, Davis was wary of comparisons between the “star monks” and the Meddling Monk, who had last appeared less than a year earlier in The Daleks' Master Plan. Davis recommended that Pedler instead look to his own experiences to inspire a different sort of antagonist. One of Pedler's areas of professional concern was medical techniques which involved the replacement of human limbs and organs with machines: so-called “cybernetics”. Pedler envisaged a race of creatures which had taken this practice to its logical extreme, and had become more machine than man; he christened them Cybermen.

When Kit Pedler fell badly ill, Gerry Davis agreed to help write The Tenth Planet

With Davis' encouragement, Pedler began to turn his ideas into a storyline. The Tenth Planet -- a title suggested by Pedler's wife -- was commissioned on May 17th. About a month later, Pedler fell badly ill and had to spend time in hospital. Davis agreed to assist Pedler in writing the serial, taking a co-writing credit on the final two episodes; copyright on the Cybermen would be split equally between the authors. Permission was received from the BBC for Davis' contribution on June 29th. As it turned out, Davis basically wrote the first draft of each script, concentrating on the action elements. Pedler then wrote a second draft, filling in more scientific details. The pair cooperatively completed a third and final draft.

Not long after The Tenth Planet was greenlighted, Davis and producer Innes Lloyd finally gained approval from their superiors to replace William Hartnell as the Doctor. Hartnell's health was deteriorating -- he suffered from arteriosclerosis -- and he had become increasingly difficult to work with on-set. To make matters worse, Doctor Who's ratings had dropped alarmingly since the start of Season Three, and it was felt that a new star might help reverse the trend. Davis posited that, since the Doctor was an alien, he could die and come back to life in a new body; Lloyd expanded on this idea, suggesting that this “renewal” could be a regular ability of the Doctor's, to transform himself from an elderly man to a younger one.

By the end of June, Lloyd and Davis had approached Patrick Troughton about taking over the role of the Doctor while Troughton was filming The Viking Queen in Ireland. Troughton was a well-known character actor, with credits including a variety of horror films in addition to numerous television appearances, ranging from The Old Curiosity Shop to Dr Finlay's Casebook to Coronation Street. Although he was interested in the part, Troughton was wary of committing himself to such a demanding and well-publicised role, as well as to a programme which had already been on the air for three years. The actor therefore deferred his decision to later in the summer.

William Hartnell agreed that it was time for him to leave Doctor Who

Soon thereafter, Lloyd spoke with Hartnell himself about the situation, and Hartnell agreed that it was time for him to leave Doctor Who. Although he was disappointed to have to move on from a programme for which he held such affection, Hartnell was cheered by the possibility of Troughton being his replacement, and also by the notion that the new Doctor would be characterised much differently from his own version. Hartnell was contracted for the first four episodes of Doctor Who's fourth production block, these comprising Serial DD: The Tenth Planet. (This would be the second story broadcast as part of Season Four, however, as The Smugglers had been held over from the end of the previous recording slate.) The storyline for Pedler and Davis' adventure was suitably amended to incorporate the change of lead actor at its conclusion. On August 2nd, Hartnell's imminent departure was announced to the press. That same day, Troughton signed a contract to appear in twenty-two episodes as the new Doctor, covering five serials.

The director assigned to The Tenth Planet was Derek Martinus, who had previously handled Galaxy 4. Responsibility for designing the Cybermen fell to costume designer Sandra Reid. Reid's realisation of Pedler and Davis' creations was rather different from the authors' description of the Cybermen. In the scripts, their faces were to be human (albeit all rather similar), with a metal plate under their hair. Their hands were also to be human, although their arms would be transparent, made up of rods and lights. A movable arm was also to extend from each Cyberman's chest unit, an accessory considered too costly to implement. (Additionally, The Tenth Planet would be the only time in Doctor Who's history that the Cybermen would be given personal names like Krang, Talon and Jarl.)

Model filming took place at the Ealing Television Film Studios on August 30th. Regular filming then occurred there over the next three days for material set on the Antarctic plain. Michael Craze found this work difficult, as he had just undergone surgery to remove a bone chip from his nose (during which he suffered a burst blood vessel which nearly cost him his life) and the jabolite “snow” blown around the film stage irritated his nose badly. Nonetheless, Craze was undeterred from asking out production assistant Edwina Verner, whose job it was to throw the jabolite into the wind machine -- and the two would subsequently marry.

William Hartnell became ill with bronchitis, so the Doctor would now collapse at the start of episode three

Work then shifted to videotape at Doctor Who's regular home of Riverside Studio 1. Unlike the programme's first three seasons, however, it had been decided that for the fourth production block, recording would take place on Saturdays rather than Fridays. This meant that rehearsals could begin on Tuesdays, freeing up Monday for film work for the next serial in production; up to this point, actors had to be released from rehearsals in order to be available for filming. As such, the first episode of The Tenth Planet was taped on Saturday, September 17th. As with The War Machines at the end of Season Three, Bernard Lodge had designed a special animation sequence to announce the story title, episode number and author. Unfortunately, for this installment, Pedler's first name was incorrectly given as “Kitt”.

Following the completion of episode two on September 24th, Hartnell became ill with bronchitis. Fortunately, the script for part three already involved the ailing Doctor resting away from the action for much of its length. Davis amended this to have the Doctor collapse in the very first scene. He shared the Doctor's dialogue between Ben -- relating things that the Doctor had told him -- and Barclay, who took on the more technical dialogue. Hartnell was given the week off and Gordon Craig, who had doubled for him in the Ealing material, played the unconscious Doctor on the recording day, October 1st. Lodge's animation was again marred by a typographical error, misspelling Davis' surname as “Davies”.

October 8th marked the end of William Hartnell's tenure on Doctor Who

October 8th marked the end of Hartnell's tenure on Doctor Who. The first scene recorded on this day was the renewal sequence itself. Originally, this would have simply seen Hartnell collapse on the floor of the TARDIS console room with his cloak covering his face; in the first episode of the next story, The Power Of The Daleks, the cloak would have been pulled back to reveal Troughton. However, vision mixer Shirley Coward was able to design a way to actually depict the renewal. This took advantage of a malfunctioning mixing desk, which tended to cause the image to flare noticeably, to create an effect by which the image of Hartnell became overexposed almost to a white-out, then settled down again to reveal Troughton's countenance. Troughton therefore was asked to sign a new contract on September 16th to appear in the episode. Once this was completed, the remainder of part four was taped, whereupon the cast and crew retired to a farewell party in Hartnell's honour at Lloyd's home.

Despite his poor health, Hartnell continued to act both in television (including episodes of No Hiding Place and Softly, Softly) and in theatre. His physical prowess continued to diminish, however, as did his memory, and so by the Seventies he was forced to retire from the profession he loved. During his time away from the series, he rarely watched Doctor Who, as the circumstances surrounding his departure from the series had been very upsetting. Nonetheless, he agreed to return to Doctor Who in 1972 for the tenth-anniversary story The Three Doctors, though his ill health meant that his involvement was far more limited than he had originally aspired. The Three Doctors turned out to be Hartnell's final performance. Crippled by a series of strokes, William Hartnell passed away in his sleep on April 23rd, 1975.

  • Doctor Who: The Handbook: The First Doctor by David J Howe, Mark Stammers and Stephen James Walker (1994), Virgin Publishing, ISBN 0 426 20430 1.
  • Doctor Who: The Sixties by David J Howe, Mark Stammers and Stephen James Walker (1992), Virgin Publishing, ISBN 1 85227 420 4.
  • Doctor Who Magazine #214, 6th July 1994, “Archive: The Tenth Planet” by Andrew Pixley, Marvel Comics UK Ltd.
  • Doctor Who Magazine Special Edition #7, 12th May 2004, “Bye Bye Blues” by Andrew Pixley, Panini Publishing Ltd.

Original Transmission
Episode 1
Date 8th Oct 1966
Time 5.52pm
Duration 23'08"
Viewers (more) 5.5m (77th)
· BBC1 5.5m
Appreciation 50%
Episode 2
Date 15th Oct 1966
Time 5.50pm
Duration 23'15"
Viewers (more) 6.4m (57th)
· BBC1 6.4m
Appreciation 48%
Episode 3
Date 22nd Oct 1966
Time 5.54pm
Duration 23'31"
Viewers (more) 7.6m (46th)
· BBC1 7.6m
Appreciation 48%
Episode 4
Date 29th Oct 1966
Time 5.51pm
Duration 24'02"
Viewers (more) 7.5m (48th)
· BBC1 7.5m
Appreciation 47%

Dr Who
William Hartnell
Anneke Wills
Michael Craze
General Cutler
Robert Beatty
Dudley Jones
David Dodimead
Alan White
Earl Cameron
Shane Shelton
American Sergeant
John Brandon
Steve Plytas
Radar Technician
Christopher Matthews
Reg Whitehead
Harry Brooks
Gregg Palmer
Geneva Technician
Ellen Cullen
TV Announcer
Glenn Beck
Cybermen Voices
Roy Skelton
Peter Hawkins
R/T Technician
Christopher Dunham
Terry Cutler
Callen Angelo
Harry Brooks
Reg Whitehead
Gregg Palmer

Written by
Kit Pedler
Gerry Davis (episodes 3, 4)
Directed by
Derek Martinus
Produced by
Innes Lloyd

Title music by
Ron Grainer and
the BBC Radiophonic Workshop
Costumes by
Sandra Reid
Make-up by
Gillian James
Howard King
Adrian Bishop-Laggett
Story Editor
Gerry Davis
Peter Kindred

Archive Holdings
Episodes Missing
Episode 4
Clips Extant
Episode 4 (1'18" in 15 clips)
Telesnaps Surviving
Episode 4

Updated 26th March 2018