The TARDIS materialises on board a spaceship, the Silver Carrier, where the Doctor and Jamie are attacked by a Servo Robot. Jamie manages to contact a nearby space station known as the Wheel and they are rescued. Meanwhile, the Silver Carrier discharges some Cybermats, which also travel to and enter the station. These pave the way for the penetration of the station by Cybermen, who intend to use its direct radio link with Earth as a beacon for their invasion fleet.

The Doctor sends Jamie and a young woman named Zoe Heriot over to the Silver Carrier to fetch the TARDIS's vector generator rod. Meanwhile he manages to free the Wheel's crew from the Cybermen's hypnotic control and to destroy all the Cybermen on the station.

When Jamie and Zoe return, he installs the rod in the station's X-ray laser, making it powerful enough to destroy the Cyber-fleet. An approaching force of space-walking Cybermen is also vanquished.


The explosion of the mercury fluid links forces the Second Doctor and Jamie McCrimmon to evacuate the TARDIS to avoid mercury fumes and, until the mercury can be replaced, the craft is marooned. They find themselves on a space vessel deserted apart from a Servo-Robot. The robot detects the intruders and in response redirects the rocket from aimless wandering, sending it on a course, and the shock of change causes the Doctor to hit his head, briefly concussing him. The robot also releases a group of egg-shaped white pods into space, and the mysterious things direct themselves toward a nearby spaceship shaped like a giant wheel, attaching themselves to its exterior by a seeming act of will. When the robot becomes aggressive, Jamie succeeds in destroying it, but the Doctor’s condition worsens and he collapses.

The Wheel is an Earth space station observing phenomena in deep space and is staffed with a small international crew. The crew members are concerned by the sudden drops in pressure which, unbeknownst to them, coincide with the pods attaching themselves to the exterior of the Wheel. Controller Jarvis Bennett is also worried that the Silver Carrier, a missing supply vessel eighty million miles off course, has suddenly turned up nearby and is not responding to radio contact. He decides to destroy it with the Wheel’s powerful X-Ray laser and is only prevented from doing so when they hear a deafening burst of noise from the vessel. Jamie has managed to alert them to his presence aboard the Carrier and in a short time he and the unconscious Doctor are both rescued and taken aboard the Wheel. While the resident medic, Doctor Gemma Corwyn, sees to the Doctor, Jamie is given a guided tour by the sparky young para-psychology librarian, Zoe Heriot. Bennett remains suspicious of the new arrivals, fearing they could be saboteurs opposed to the space program. He decides to use the X-Ray Laser on the Carrier now that the two refugees have been rescued, little realizing the TARDIS is still on board. Jamie intervenes to sabotage the laser, which only further infuriates Bennett, especially as the potential meteor shower heading for the Wheel – and they now have no way to repel it. When the Doctor recovers in the sickbay he does not approve of this action. He also remains groggy and unclear, but convinced a major danger lurked on the Silver Carrier. He calculates that the ship did not drift to their sector but was deliberately piloted there. The Wheel’s crew, however, are more concerned with the impending meteor shower.

On board the Carrier, meanwhile, two large pods have split open to reveal two Cybermen inside. The small pods they sent to the Wheel contained Cybermats and these have been set to work in consuming bernalium rods in the Wheel’s stores. The bernalium is essential to power the X-Ray Laser. The Cybermen have deliberately engineered the star in Messier 13 to go nova, thus forcing the Wheel crew to look for their bernalium and find it missing. When this happens the Cybermen are sure the crewmen will instead come to the Silver Carrier for the bernalium, which can then be transported into the Wheel – with a surprise inside.

An engineer called Bill Duggan indeed has noted the depleted stocks and the presence of the Cybermats. His slowness in reacting allows another crewman, Kemel Rudkin, to fall victim to the Cybermats. Jarvis Bennett overreacts with panic to this state of affairs, briefly stripping Duggan of his position and imposing tighter controls. The Doctor has a more practical solution – he uses the X-Ray machine to scan inside a pod that has been found but cannot be opened. The Cybermat within is easy for him to identify, but Bennett does not accept the danger. Indeed, medic Gemma Corwyn, who has formed an alliance with the Doctor, fears for Bennett’s mental state as he seems unable to deal with escalating events. Over time his behaviour seems to be becoming more and more bizarre and detached from reality.

He has sent two crewmen to the Silver Carrier, Laleham and Vallance, and the two are taken over by the Cybermen and used to prepare the bernalium crates for the Wheel with the two Cybermen hidden inside. This ruse works and the crates are soon aboard the Wheel, with Duggan and his colleague Leo Ryan glad to have access to a new power supply for the X-Ray Laser, which they are slowly managing to repair. An engineer called Chang is killed by the emerging Cybermen when he is sent to fetch the new bernalium supply. They dispose of his body in the waste incinerator. Laleham and Vallance arrive at the Laser with the supply of bernalium for Duggan, who soon falls victim to the same mind control process and becomes the third agent of the Cybermen on the Wheel. He is sent to destroy the communications unit and manages to do so before being gunned down.

The Doctor has meanwhile deduced that the fortuitous supply of bernalium has a deeper significance. He has also worked out the late Duggan was under mind control and instructs Dr Corwyn to use a basic transistor system attached to each of the crewmen as a means of repelling this technique. A further step forward is taken when the crew use a sonic wave to disable and kill the Cybermats on the Wheel, but it is also clear to the Cybermen are at large and proceeding with their plans. The death of Laleham is no obstacle as another engineer, Flannigan, is found to replace him. The Cybermen have invested time in repairing the X-Ray Laser, evidently needing it ready for use. Thus when the meteorites are finally due to hit they can be deflected and obliterated. The Cybermen need the Wheel intact as they are planning to use it as a launching point for an invasion of Earth, desperate for the planet’s mineral wealth. The Wheel's radio beam will enable them to do this.

The human crew have managed to fully repair the X-Ray Laser and use it to defend. They are one by one picked off by the Cybermen or the agents. Gemma Corwyn dies trying to prevent the Cybermen from damaging the oxygen supply on the Wheel. Shocked back to consciousness by her death, the insane Jarvis Bennett is mowed down when he seeks revenge. Leo Ryan assumes control as the Doctor warns there is a vast Cyberman spacecraft heading for the Wheel.

The Doctor has decided he needs the time vector generator which he removed from the TARDIS. Jamie and Zoe are chosen for a space-walk to the Silver Carrier and return with the prize. Flannigan tries to overpower them when they get back to the Wheel, but he in turn is overwhelmed by Leo and Enrico Casali, the communications officer, and his conditioning is broken. The Doctor also manages a triumph, electrocuting one of the Cybermen and confirming to himself the full nature of their plans. He uses the time vector generator to boost the power of the X-Ray Laser and this succeeds in destroying the advancing Cybership. A troop of Cybermen space-walking to the Wheel are also dispensed with, while Jamie and Flannigan free Vallance and destroy the remaining Cyberman inside the Wheel.

With the invasion repelled the Doctor and Jamie returns to the Silver Carrier with the mercury they need to repair the TARDIS. They are accompanied by Zoe, who quietly stows away as the time vessel departs. She is determined to stay and so, to warn her of the dangers ahead, the Doctor uses a mental device to project images from his mind which tells her of his and Jamie's encounter with the Daleks in their search for the Dalek Factor...




  • The Doctor carries gets his pseudonym of John Smith from Jamie, who sees it as a brand name on a medical container.
  • Zoe Heriot is the Wheel's parapsychology librarian (which means that she's received brainwashing-like training in logic and memory), an astrophysicist, an astrometricist first class, and a major in pure maths. History is a weak area for her.
  • The TARDIS still has problems with its fluid links evaporating, and needs more mercury.
  • The Time Vector Generator is a rod that makes the TARDIS dimensionally transcendental (it powers the connection between the two dimensions) and is a powerful energy source, able to seal, burn, power or zap things, and giving out huge amounts of radio interference.
  • Cybermats can cut into metal hulls and re-seal the holes undetected. They corrode bernalium, they're vulnerable to quick setting hyperoxide plastic. They tune into brainwaves to find their targets, but can be confused by oscillating radio signals.
  • The humans have never heard of the Cybermen or the Daleks.

Story Notes

  • The working title for this story was; The Space Wheel.
  • Patrick Troughton makes no appearance in Episode 2 as he was on holiday during the week when it was recorded. The Doctor is seen only as an unconscious figure, with Chris Jeffries doubling for Troughton.
  • This story is the first to have an incidental music score as well as sound effects provided by the BBC's Radiophonic Workshop.
  • Only Episodes 3 and 6 exist in the BBC Archives. Episode 6 was transmitted from a 35 mm film print and retained in the BBC Film Library (although Episode 5 was not). A private collector obtained a copy of Episode 3 and returned it in 1983.

Cast Notes

  • Patrick Troughton did not appear in episode 2 as he was on holiday. Thus, a body double was used to substitute for the unconscious Doctor.
  • Deborah Watling's appearance in episode 1 was a recap from the end of the previous story Fury from the Deep. Unusually, Deborah received an on-screen credit for this appearance.
  • Michael Goldie previously played Craddock in The Dalek Invasion of Earth (1964), whilst Kenneth Watson had played Craddock in the theatrical version of this story, Daleks - Invasion Earth 2150 AD (1966).


  • Episode 1 - 7.2 million viewers
  • Episode 2 - 6.9 million viewers
  • Episode 3 - 7.5 million viewers
  • Episode 4 - 8.6 million viewers
  • Episode 5 - 6.8 million viewers
  • Episode 6 - 6.5 million viewers


  • This story went considerably over budget. (It was one of the few stories of the second Doctor's era to come in under budget.)
  • There is a suspenseful scene in which the two Cybermen menace Zoe in the Wheel's library. (There is no such scene. The photographs that exist of this were specially posed for publicity purposes only.)
  • Only two Cyberman costumes were used in the making of this story. (A third was put together from stock for the sequence in Episode 6 where a force of Cybermen space-walk toward the Wheel.)
  • Eric Flynn, who plays Leo Ryan in this story, was the son of Hollywood film star Errol Flynn. (Eric Flynn is not related to Errol Flynn)


The story that was originally planned for this spot in the production schedule was to have portrayed a Dalek/Cybermen confrontation. Although this was disallowed by Terry Nation, he did give an important concession in return. He allowed for future Dalek stories — something that was not seen as certain at the time. His precondition for this permission would remain in effect the rest of his life: he had to be given the first right of refusal to write the script on any proposed Dalek storyline.[1] Meanwhile, Kit Pedler, whose involvement with the original idea for a Cyber/Dalek war is uncertain, brought an entirely different Cybermen story to the table in the form of "The Space Wheel". He was teamed with David Whitaker to bring this idea to script form.

The idea of a Cyber/Dalek war festered in the minds of both Doctor Who fans and production staff alike. It would not be realized until the 2006 episode, "Doomsday".

Filming Locations

Discontinuity, Plot Holes, Errors

  • 'Wheel in space' is almost certainly ahead of Moonbase. So if "every child," knows Cybermen existed in 2070, and this is future, why does Jarvis say the idea of Cybermen is "rubbish"?
  • How can the Doctor show Zoe a memory of a scene where he was not present


  • A clip from The Evil of the Daleks is used for a sequence where the Doctor shows Zoe, (in the TARDIS), what she may face if she travels with him. This was used as a way to introduce a repeat of The Evil of the Daleks the week following the original broadcast of The Wheel in Space. However, the clip used is actually from the end of Episode One, rather than the beginning of the existent Episode Two, meaning that this story contains a few frames of footage from the currently missing Episode One of The Evil of the Daleks.
  • Ironically, Zoe would never encounter the Daleks on television; decades later, the Big Finish Productions audio story Fear of the Daleks would tell of an encounter between Zoe and the Daleks, set immediately after the Doctor's telepathic re-run.
  • The Time Vector Generator also plays a part in MA: Invasion of the Cat-People NA: Birthright and Iceberg.

DVD, Video and Other Releases


Wheel in Space novel
Main article: The Wheel in Space (novelisation)

External Links


  1. Shannon Sullivan's exploration of The Wheel in Space

Template:Season 5

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