DD. The Tenth Planet

Season Four - 1966/1967

Story Editor: Gerry Davis
Writers: Kit Pedlar and Gerry Davis (uncredited 1-2)
Director: Derek Martinus
Produced by: Innes Lloyd
Designer: Peter Kindred
Incidental Music: Stock


At the South Pole Base of International Space Command, in 1986, a team of people are monitoring the launch of the Zeus-IV rocket. It seems to be a routine launch, and elsewhere in the centre everything else is running smoothly, although a visual check outside the base just misses the materialisation of the TARDIS.

The TARDIS instruments tell the Doctor of the conditions outside the TARDIS, and whilst Ben and Polly dress in thick coats the Doctor chooses a simple cape and hat to keep him warm. Polly is eager to investigate and soon spots a periscope from a submerged base. Inside the base the Sergeant in charge of the periscope spots Polly and asks his colleague Tito to check it. Tito doesn't believe there are people outside - but becomes interested when the Sergeant says one of them is a woman. The soldiers in the base quickly mobilise and fetch the  Doctor, Ben and Polly into the base at gunpoint.

Tito starts to ask questions to the Doctor, Ben and Polly, and the Sergeant tells him to call for the commanding officer - General Cutler. Cutler isn't impressed, and only Ben is able to give a name and rank, and Cutler asks why he is not with his ship. Cutler orders his men to talk the Doctor, Ben and Polly to the observation room where he can keep an eye on them. Ben and Polly, being from the 1960s, are in awe at the small number of people that are required on the base, and the fact that computers are taking over. When Ben asks if they have got to the moon yet one of the soldiers says that they got to the moon long ago, and that the current mission is a routine atmosphere testing probe.

The missions should be a routine mission, but the rocket is having problems and is off course. Williams, in the rocket, is told to take a measurement using the position of Mars to determine their position. Williams then discovers that there is another - tenth - planet nearby. In the rocket Shultz has a look and also sees the new planet. When Shultz tries to radio back to the base he is told he is faint, and asked to increase his communications power, even though it is high. The fuel cells are also starting to run low.

In the base scientists Dyson and Barclay spot the new planet, and realising that this is interfering with the Zeus-IV rocket, and Barclay opts for an emergency splashdown for the rocket and sends the new co-ordinates to the rocket. Williams and Shultz are having problems functioning properly, and Barclay initially thinks it could be fatigue after spending time in space. The gravity from the tenth planet is affecting the rocket's descent and flight path. The Doctor tries to hand General Cutler a note telling him what he will see if he looks at the planet. On a monitor they can all see the tenth planet, and the land masses look so similar to Earth Cutler thinks it is a reflection of Earth. When Barclay looks at the note it describes exactly what they are seeing.

Cutler thinks it is just a confidence trick, but Barclay wants to know how the Doctor already knows about the tenth planet. The Doctor explains that millions of years ago Earth had a twin planet, and that soon they should expect visitors. Cutler demands to know from the Doctor how come a routine space shot goes wrong, a tenth planet appears, and so does the Doctor claiming to know all about it. Whilst he is questioning the Doctor he orders a sergeant and Tito to search the TARDIS, which means going onto the Antarctic surface.

The sergeant sends Tito back to get some cutting equipment to get into the TARDIS, and is attacked by silver men who have landed in small pod. When Tito goes back outside he is also attacked.

Around the world the new planet has been noticed, and television news is reporting the discovery of the planet. The news reporter tells people that whilst the planet is getting closer it is not going to collide, and asks people not to panic.

Inside the polar base the silver men make their way to the command centre. A soldier is killed when he tries to approach one of them. One of the men tells Cutler that the rocket will not be returning to Earth. The man then tells Barclay about the tenth planet - Mondas, and ancient name for Earth, and tells him the name of their race: Cybermen. On Mondas the scientists realised that their lifespans were getting shorted, and so set about replacing body parts until all that is left are robots with living brains. The Cyberman also explains that some weaknesses such as emotions.

At International Space Command in Europe the situation is being monitored. As Mondas gets closed Earth is losing energy. When they receive a distress signal from the polar base the director, Wigner, tries to get hold of the base by radio. In the base the Cyberman is not happy that Cutler sent a signal to Europe, and demands he sends another message to say everything is okay. When Cutler refuses he is stunned.  When the Cyberman threatens to destroy equipment Barclay relents and tells Europe that the situation is under control.

When two Cybermen take away the dead body of the soldier Ben grabs hold of his gun. A Cyberman takes the gun from Ben and shows its strength by bending the machine gun before Ben is taken away and locked in a projection room.  Using the projector on the door Ben calls the Cyberman inside, hoping to blind it. It is briefly blinded, long enough to grabs its weapon. When the Cyberman advances on Ben he fires the weapon.

In the command centre the Cyberman, with no emotions, states that everyone will be returning back to Mondas to be converted into Cybermen as well. The Doctor and Polly struggle to comprehend how the Cyberman can be so unemotional, and it tells them that on Mondas they will have no need of emotions.  Unseen Cutler recovers, and takes the weapon from Ben when he arrives. Cutler fires on the Cyberman, and contacts Geneva to tell them about the Cybermen and Mondas. When warned Wigner immediately places military bases around the world on alert. Wigner the tells Cutler that a single astronaut was sent up to help Shultz and Williams in Zeus-IV, and that he should try to contact him. The astronaut is a volunteer: and is Cutler's son.

As the base starts to track Cutler's son's capsule they also detect a number of unidentified objects in formation heading for Earth. As tensions rise the Doctor collapses, and Ben and Polly take him to a medical bay as Cutler establishes contact with his son, and tells him about the problems that have been happening, and how he won't be meeting up with Williams and Shultz.

Ben and Polly, after checking he is okay, leave the Doctor resting and return to the command centre in time to hear General Cutler talking about getting authorisation to use the Z-Bomb - a bomb that is powerful enough to destroy Mondas. There are up to three Z-Bombs around the world, and the polar base has one, and the means to deliver it to Mondas. Wigner tells General Cutler not to use the XZ-Bomb, but authorises him to do whatever is necessary to stop the Cybermen. General Cutler tells Barclay to start the countdown for the Z-Bomb, and Ben tries to get him to wait and orders Ben to be locked up with the Doctor whilst he and Dyson go to set the fuse in the bomb.

Barclay and Polly help Ben to escape and tells Ben how to get to the Z-Bomb, and how to sabotage the Z-Bomb rocket. Ben gets to thge Z-Bomb but is caught by General Cutler and taken back to the commad centre. The Z-Bomb countdown appears to proceed normally, until the moment of launch when it powers down.  The Doctor, appearting recovered, arrives just in time. Furious General Cutler orders the Doctor, Ben and Polly to  be held at gunpoint along with Barclay.

Lieutenant Cutler is able to get through from his Zeus-V craft, and tells them something is happening with Mondas, and the Doctor says it is because Mondas cannot contain all the energy it is draining from Earth. Lieutenant Cutler's craft loses power, and contact, and General Cutler turns on the Doctor. He is about to shoot when more Cybermen appear. Cutler fires at one of them, but is killed.

The Doctor talks to the lead Cyberman, saying that by preventing the missile launch they saved Mondas. The Doctor says he knows why the Cybermen have come to Earth, as Mondas is dying, and asks the Cybermen to consider staying on Earth as an ally, and the Cyberman confers with the other Cybermen. The Doctor is playing for time, and the Cyberman says it will not discuss terns whilst a warhead is aimed at Mondas. Barclay says he can disarm the warhead. Polly and the Doctor are taken to the Cybermen's spaceship as hostages.

Geneva tries to contact the polar base, and the Doctor answer. Geneva tells the Doctor that Cybermen have landed all over the Earth and the Doctor hears about a second objective, and realises the Cybermen plan to use the Z-Bomb to destroy Earth. He communicates with Ben and Barclay and tells them not to help the Cybermen. Inside the Z-Bomb chamber it's Ben who asks the obvious question: Why do the Cybermen need their help at all? They are stronger and could easily move the bomb and they are more advanced so could easily repair it. Barclay thinks it could be that they are afraid of the radiation. Ben lures one inside the room and it immediately collapses.

By holding onto rods from the base's nuclear reactor Ben, Barclay and Dyson had weapons they can fight the Cybermen with. When more Cybermen come to the room they are killed. With the Cybermen's guns they break back into the command centr4e. On a screen they seen Mondas disintegrate. The Cybermen, depending on Mondas for power, all collapse.Free from Mondas Lieutenant Cutler's craft regains full power and is able to get back to Earth.

On the spaceship the Doctor and Polly can feel vibrations. Polly thinks the ship is taking off, but the Doctor thinks that as the ship draws its power from Mondas it could be Mondas that is causing the vibrations. With the base staff clearing up Ben makes it to Cybermen's ship to free the Doctor and Polly. Polly, scared, seems okay, but the Doctor is acting strange. He says he must get back to the TARDIS immediately. When Ben and Polly get back to the TARDIS they find the Doctor collapsed on the floor. The TADIS de-materialises as the Doctor starts to regenerate.

Regular Cast

  • Ben Jackson: Michael Craze
  • Polly Wright: Anneke Wills

Guest Cast

  • General Cutler: Robert Beatty
  • Dr. Barclay: David Dodimead
  • Dr. Ernest John Dyson: Dudley Jones
  • Radar Technician: Christopher Matthews
  • Wigner: Steve Plytas
  • Major Dan Shultz: Alan White (1-2)
  • Colonel Williams: Earl Cameron (1-2)
  • Private Tito: Shane Shelton (1)
  • American Sergeant: John Brandon (1)
  • Krail: Reg Whitehead (2)
  • Talon: Harry Brooks (2)
  • Shav: Gregg Palmer (2)
  • Cyberman Voices: Roy Skelton (2,4), Peter Hawkins (4)
  • Geneva Technician: Ellen Cullen (2-4)
  • Television Announcer: Glenn Beck (2)
  • Lt. Terry Cutler: Callen Angelo (3-4)
  • R/T Technician: Christopher Dunham
  • Krang: Harry Brooks (4)
  • Jarl: Reg Whitehead (4)
  • Gern: Gregg Palmer (4)
  • Cybermen: (all 2,4) John Haines, John Knott, Bruce Wells
  • R/T Technician: Nicholas Edwards
  • Double for the Doctor: Gordon Craig (3)
  • Double for Ben: Peter Pocock (3)
  • Doctor Who: Patrick Troughton
  • Secretary: Sheila Edwards
  • Corporal: Alec Coleman
  • Soldiers: Freddie Eldrett, Nick Hilton, Terence Jones, Ken McGarvie, Roy Pierce, Peter Pocock
  • Officers: Gordon Lang, Richard Lawrence, Morris Quick
  • Engineers: Freddie Eldrett, Roy Pierce

Original broadcast on the BBC

Channel Title Date Viewers Rating
BBC 1 131. Episode 1 Saturday, October 8, 1966 5:50 PM - 6:15 PM 5.5M 50%
BBC 1 132. Episode 2 Saturday, October 15, 1966 5:50 PM - 6:15 PM 6.4M 48%
BBC 1 133. Episode 3 Saturday, October 22, 1966 5:50 PM - 6:15 PM 7.6M 48%
BBC 1 134. Episode 4 Saturday, October 29, 1966 5:15 PM - 5:40 PM 7.6M 47%


  • Ealing Television Film Studios
  • Riverside Studio 1


Part 1: The credits at the end of this episode spell Kit Pedlar's name as Kitt.

Part 3: The credits at the end of this episode spell Gerry Davis's name as Davies.


Part 3: William Hartnell does not appear in this episode.

This is the last Hartnell story, introducing the revolutionary concept of regeneration.

An unusual computer style graphic sequence is used to produce all the credits in the opening titles and end credits.

This programme was filmed, and is set, before Pluto was demoted from planet status - otherwise Mondas would have been the Ninth Planet.