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UFO is a 1970 British television science fiction series about an alien invasion of Earth, created by Gerry Anderson and Sylvia Anderson with Reg Hill, and produced by the Andersons and Lew Grade's Century 21 Productions for Grade's ITC Entertainment company.
UFO first aired in the UK and Canada in 1970 and in US syndication over the next two years. In all, 26 episodes, including the pilot, were filmed over the course of more than a year, with a five-month production break caused by the closure of the MGM-British Studios in Borehamwood, where the show was initially made.
The Andersons had previously made a number of very successful children's science fiction series using marionettes, including Supercar, Fireball XL5, Stingray, Thunderbirds, and Captain Scarlet and the Mysterons. They had also made one live-action science fiction movie, Doppelgänger, also known as Journey to the Far Side of the Sun, and now felt ready to move into live-action television and aim at a more adult market.
UFO was the Andersons' first totally live-action TV series. Despite the assumption of many TV station executives, the series was not aimed at children but was intended for an older audience; many episodes featured adult themes such as adultery, divorce, and drug use. Most of the cast were newcomers to Century 21 although star Ed Bishop had previously worked with the Andersons as a voice actor on Captain Scarlet and The Mysterons.
The show's basic premise is that in the near future – a fictional version of 1980 (a date indicated in the opening credits) – Earth is being visited and attacked by aliens from a dying planet and humans are being covertly harvested for their organs by the aliens. The show's main cast of characters are members of a secret, high-technology international agency called SHADO (an acronym for Supreme Headquarters, Alien Defence Organisation) established to defend Earth and humanity against the mysterious aliens and learn more about them.
To defend against the aliens, a secret organisation called SHADO, the Supreme Headquarters, Alien Defence Organisation, is established. Operating behind the cover of the Harlington-Straker Studios movie studio in England, SHADO is headed by Commander Edward Straker (Ed Bishop), a former United States Air Force colonel and astronaut who poses as the studio's chief executive.
Establishing the main character as a studio executive was a cost-saving move by the producers: the studio was the actual studio where the series was being filmed, originally the MGM-British Studios and later Pinewood Studios – although the Harlington-Straker studio office block seen throughout the series was actually Neptune House, a building at the former British National Studios in Borehamwood that was owned by ATV. Pinewood's studio buildings and streetscapes were used extensively in later episodes, particularly "Timelash" and "Mindbender", the latter featuring scenes that showed the behind-the-scenes workings of the UFO sets when Straker briefly finds himself hallucinating that he is an actor on a TV series and all his SHADO colleagues are likewise actors.
Typical of Anderson productions, the studio-as-cover idea was both practical and cost-effective for the production and provided a ready-made vehicle for the viewer's suspension of disbelief. It removed the need to build an expensive exterior set for the SHADO base and combined the all-important "secret" cover (concealment and secrecy are always central themes in Anderson dramas) with the trademark ring of at least nominal plausibility. A studio was a business where unusual events and routines would not be remarkable or even noticed. Comings and goings at odd times, the movement of vehicles, equipment, people and material would not excite undue interest and could easily be explained away as "sets", "props", or "extras".