The Ambassadors of Death is the third serial of the seventh season of the British science fiction television series Doctor Who, which was first broadcast in seven weekly parts on BBC1 from 21 March to 2 May 1970. The serial's script was credited to David Whitaker but completed primarily by Malcolm Hulke and Trevor Ray. It was directed by Michael Ferguson.
The serial is set in London, Hertfordshire and the Earth's orbit. In the serial, the alien time traveller the Third Doctor (Jon Pertwee) and the international organisation UNIT investigate the disappearance of astronauts who have lost contact with Earth. They become involved in a conspiracy and meet alien ambassadors who have arrived on Earth.
Plot
The United Nations Intelligence Taskforce, alongside Ralph Cornish (Ronald Allen)— Professor and Controller—attempt to make contact with the missing Mars Probe Seven and its two astronauts, who lost contact with Earth eight months earlier. When the recovery crew returns to earth, it is captured by General Charles Carrington (John Abineri), also abducting the missing astronauts. Carrington is now introduced to the Doctor by Sir James Quinlan (Dallas Cavell), the Minister for Technology, as head of the newly formed Space Security Department. Carrington says his actions were to protect the astronauts, as they have been infected with contagious radiation. Quinlan states the government did not want the public to become panic-stricken and reveals that Carrington has been acting with government authority. The Doctor believes the real astronauts are still in orbit, and that the three space suits contain alien beings.
An intelligent but ruthless criminal named Reegan (William Dysart) engineers the kidnapping of Liz Shaw to aid his own scientist, Lennox (Cyril Shaps), in keeping the aliens alive. Reegan sends the creatures to the Space Centre to kill Quinlan. Liz helps Lennox escape, and he tries to reach the Brigadier, but Reegan finds and kills him with a radioactive isotope.
Cornish is determined to launch another spacecraft to retrieve his astronauts from the Mars Probe capsule in Earth orbit. The Doctor volunteers to pilot the rocket himself, but its safe travel is sabotaged, and nearly kills the Doctor. In orbit, the recovery capsule is taken prisoner by an alien spaceship. Aboard the craft, an alien being explains the humans are being held pending the safe return of the alien ambassadors, who have been sent to Earth to make peaceful contact with mankind. However, the alien being also gives the ultimatum that they will attack should their ambassadors not be freed. The Doctor gives his personal guarantee to return the ambassadors safely.
When the Doctor touches down, he is kidnapped by Reegan, who reunites him with Liz. Reegan's paymaster, and the real organiser of the conspiracy, is revealed: General Carrington. In the previous Mars Probe Six mission, Carrington was one of the crew members; they discovered and made contact with these alien beings. Unfortunately, their contact went awry, as the radiation emitted by the creatures is lethal to humans, which killed Carrington's partner. Out of a misplaced sense of guilt and duty, The General has lured the three aliens to Earth in order to expose them on television and intends to call on the nations of the world to attack them. The use of the ambassadors to kill was done simply to arouse public opinion against them beforehand.
The Doctor manages to send a radio message, and the Brigadier and UNIT soldiers rescue him and Liz, arresting Reegan. They race to the Space Centre, where the Brigadier arrests Carrington. The Doctor arranges for Ralph Cornish and Liz to return the ambassadors to their own people so that the three human astronauts can be released.
Production
David Whitaker, despite being the sole credited writer for the serial, drafted the first three episodes only. Trevor Ray, the series' assistant script editor, completed episode one; Malcolm Hulke finalised episodes two and three, and wrote the remaining four episodes.
Director Michael Ferguson suggested amendments to the opening titles sequence for this story. The opening titles start with the normal music and graphics, yet immediately fade after the Doctor Who title caption. There is a short "teaser" for episode one, and episodes 2–7 feature a reprise of the previous episode's cliffhanger. This is followed by the cliffhanger "sting" effect, accompanied by a zoom-in on the words "The Ambassadors", concluding with "of Death", and a "zap" effect. Ferguson also recommended the sting be used to lead into the closing credits, which was retained for future stories. Along with a closing effect, the sting was added to the theme music's recording by Brian Hodgson of the BBC Radiophonic Workshop. Because it was uncomfortable for the actors, the make-up was applied shortly before they had to go on set. Geoffrey Beevers later played the Master in The Keeper of Traken (1981) and a number of Big Finish Productions audio plays. William Dysart had previously appeared in The Highlanders (1967). Peter Halliday, who provided the voices of the aliens, and also supplied the voices of the Silurians in the previous story, had first appeared in Doctor Who in The Invasion the previous season, and later appeared in Carnival of Monsters (alongside Michael Wisher), City of Death (1979) and Remembrance of the Daleks (1988). Cyril Shaps previously played Viner in The Tomb of the Cybermen (1967), and subsequently appeared with Jon Pertwee in Planet of the Spiders (1974) and with Tom Baker in The Androids of Tara (1978).