UFO (TV series)
Following poor ratings for "Joe 90" (1968–69) and the cancellation of children's espionage television series "The Secret Service" (1969) after only one series, Lew Grade approached Gerry Anderson to look into creating his first live-action TV series. Anderson worked with his wife, Sylvia, and producer Reg Hill to create a sci-fi adventure series based around UFOs. Anderson said the core idea for the series was that UFO sightings were a common issue during the late 1960s and that idea of aliens harvesting human organs came from the work of Christian Barnard and his pioneering transplant operations. The creative team initially envisioned an organisation called UFoeDO (Unidentified Foe Defence Organisation), which was to become the secret SHADO (Supreme Headquarters Alien Defence Organisation).
UFO (TV series)
Two years after the 26 episodes were completed, the series was syndicated on American television and the ratings were initially promising enough to prompt ITC to commission a second season of "UFO". As the Moon-based episodes appeared to have proven more popular than the Earth-based stories, ITC insisted that in the new season, the action would take place entirely on the Moon. Gerry Anderson proposed a format in which SHADO Moonbase had been greatly enlarged to become the organisation's main headquarters, and pre-production on "UFO 2" began with extensive research and design for the new Moonbase. These developments were not without precedent in the earlier episodes: a subplot of "Kill Straker!" sees Straker negotiating with SHADO's financial supporters for funding to build more moonbases within 10 years. However, when ratings for the syndicated broadcasts in America dropped towards the end of the run, ITC cancelled the second season plans. Unwilling to let the "UFO 2" pre-production work go to waste, Anderson instead offered ITC a new series idea, unrelated to "UFO", in which the Moon would be blown out of Earth orbit taking the Moonbase survivors with it. This proposal developed into "".