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The Invasion is the partly missing third serial of the sixth season of the British science fiction television series Doctor Who, which was first broadcast in eight weekly parts from 2 November to 21 December 1968.
In the serial, the megalomaniac Tobias Vaughn (Kevin Stoney), the head of the hugely successful electronics company International Electromatics, forms an alliance with the Cybermen to take control of Earth.
The Invasion marks the first appearance of UNIT, the second appearance of Lethbridge-Stewart (Nicholas Courtney), now promoted to Brigadier, and introduces Corporal Benton (John Levene), later to become a sergeant during the Third Doctor's era. It was the first incomplete Doctor Who serial to be released on DVD with full-length animated reconstructions of its two missing episodes.
Plot
After being fired upon, the Doctor, Jamie and Zoe land a damaged TARDIS in London and go to find Professor Edward Travers for his assistance. They discover Professor Travers has leased his house to Professor Watkins and his niece Isobel. Watkins has gone missing while working for a shadowy electronics company called International Electromatics. The Doctor and Jamie leave to investigate its head office, where they meet Tobias Vaughn, the company's Managing Director, and Brigadier Alastair Lethbridge-Stewart head of a military taskforce called UNIT, which investigates unusual activities around the world.
Taken to the company's countryside base, the Doctor and Jamie meet Watkins, who is working on a "Cerebration Mentor" device, intended to be a teaching machine. Watkins reveals that Vaughn is working with an unspecified ally and that they are planning to take over the world. Further investigation reveals this ally as the Cybermen, who intend to send a hypnotic signal through the devices produced by International Electromatics, which will incapacitate the world's population and nullify resistance. The Doctor is able to protect his companions and their UNIT allies with specially made depolarisers that neutralise the Cybermen's signal. As the Cybermen take over, the Brigadier arranges for the Doctor and company to be transported to UNIT headquarters in Geneva to help battle the invasion.
After completing production on more depolarisers, the Doctor leaves to confront Vaughn in London whilst UNIT works to stop the Cybermen. Uncovering Russian plans to launch a rocket at the ship sending the signals, Turner leads a squadron to assist them whilst Zoe helps the Brigadier predict the Cyberfleet's movements. Using British artillery, they are able to destroy the full fleet, causing the Cybermen to turn on Vaughn and decide to destroy Earth with a megatron bomb. His plans ruined, Vaughn agrees to thwart the invasion and helps the Doctor locate the homing signal. With UNIT sending troops to help, they defeat the Cybermen guarding the beacon and turn it off, though Vaughn is killed in an ambush. The megatron bomb is destroyed by an anti-missile defence rocket, while the Russian rocket destroys the Cybership broadcasting the hypnotic control signal, ending the invasion. Following the success, the Doctor and his companions leave in the TARDIS.
Production
thumb|[[Robert Sidaway (actor)|Robert Sidaway with director Douglas Camfield on location during the production]]
Originally The Invasion was going to be a six-part story under the title The Return of the Cybermen, a name shared with the working title of The Moonbase (1967). The character of Professor Travers (who appeared in the two earlier Yeti stories) was to have appeared for a third time, but the decision was made to replace him with Professor Watkins as using him would involve paying Mervyn Haisman and Henry Lincoln (who were against their characters' usage after a disagreement over rewrites of The Dominators conducted without their approval), although Travers is still referenced by name several times. The sequence where Gregory describes UNIT's attack on an IE car and then is subsequently killed by a Cyberman was written into the script after time pressures prevented the production team from filming the car attack on location. (Ian Marter, however, did reinstate the lost car attack scene in his novelisation.)
Filming
Wendy Padbury does not appear in episode 3, as she was on holiday. Frazer Hines was on a scheduled break during the last episode but did appear in a pre-recorded film insert at the conclusion.
According to Frazer Hines in an interview on the audio CD of The Invasion, Sally Faulkner's skirt kept getting blown up around her neck whilst climbing up the rope ladder to the helicopter. To avoid the same thing happening to his kilt, he remembered reading somewhere that the Queen had lead weights sewn into the hem of her skirt to stop this from happening to her. It so happened that Frazer's dresser was a keen fisherman, who sewed some lead weights into his kilt.
This was one of the first Doctor Who serials in which scenes were recorded out of order. This was due to the then-improved videotape editing technology.
Post-production
Due to director Douglas Camfield's refusal to use regular composer Dudley Simpson, Don Harper was hired to do the music for this serial. It would be Harper's only work with Doctor Who.
Cast notes
Kevin Stoney previously played Mavic Chen in The Daleks' Master Plan (1965–66) and would later play Tyrum in Revenge of the Cybermen (1975). Peter Halliday, who plays Packer, also supplied the voice of the Cyber-Director in all eight episodes of the serial, in addition to the Cybermen voices in the last four episodes. In addition, Halliday went on to do several other roles (both voice and acting) in several later serials in the series. Edward Burnham also portrays Professor Kettlewell in the Tom Baker serial, Robot (1974–75). Clifford Earl previously played the station sergeant in The Daleks' Master Plan. Sheila Dunn previously played Blossom Lefavre in The Daleks' Master Plan and would later play Petra Williams in Inferno (1970). Sally Faulkner later played Miss Tremayne in the audio play Winter for the Adept. Ian Fairbairn had previously played Questa in The Macra Terror (1967) and would later play Bromley in Inferno and Doctor Chester in The Seeds of Doom (1976), both stories directed by Camfield.