UFO is a 1970 British science fiction television series about the covert efforts of an international defence organisation (under the auspices of the United Nations) to prevent an alien invasion of Earth. It was created by Gerry Anderson and Sylvia Anderson with Reg Hill, and produced by the Andersons and Lew Grade's Century 21 for Grade's ITC Entertainment company.
A single series of 26 episodes (including the pilot) was filmed over the course of more than a year; a five-month production break was caused by the closure of MGM-British Studios in Borehamwood, where the show was initially made. Production then moved to Pinewood Studios in Buckinghamshire. UFO was first broadcast in the UK and Canada from 1970, and in the United States from 1972.