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.
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.
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.
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.
In the previous Mars Probe Six mission, Carrington was one of the crew members; they discovered and made contact with these alien beings.
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 Doctor manages to send a radio message, and the Brigadier and UNIT soldiers rescue him and Liz, arresting Reegan.
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.
[1] Location filming took place during January and February 1970 at Blue Circle Cement in Kent, Marlow Lock in Buckinghamshire, Southall Gas Works in Middlesex, and various sites in Aldershot, Hampshire.
[4] In episodes 5 and 7, John Levene reprises the role of UNIT member Benton, now promoted to Sergeant, who had first been seen in the season 6-story The Invasion.
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).
Cultural historian James Chapman has written about connections between this Doctor Who serial and earlier science-fiction TV programmes.
[9] Chapman also refers to the 1960s Gerry Anderson series Captain Scarlet and the Mysterons, whose eponymous aliens are a race of malevolent Martians.
[9] Patrick Mulkern of Radio Times noted that the script revisions caused an "uneven plot" and anticlimax, and wrote that the "narrative feels extemporised, a bumpy, sometimes thrilling ride, but one with no clear end in sight".
Club reviewer Christopher Bahn stated that The Ambassadors of Death was the "weakest" entry in a very good season, noting that it "spins its wheels" in the middle, but filled the time with impressive stunts.
[10] DVD Talk's John Sinnot rated The Ambassadors of Death three stars out of five, describing it as a "generally fun adventure" despite it being a couple of episodes too long.
He was positive towards the Doctor's characterisation and the Ambassadors, who he described as "a great low-budget creature that actually looks more menacing than silly", but felt "there are a few too many plot twists and the result is a script with some pretty major holes in it".