About the film
UFOs: Past, Present, and Future is a 1974 documentary film that examines several prominent sightings of unidentified flying objects (UFOs) from the post-war to contemporary era. It was rereleased in 1976 and 1979 under the title UFOs: It Has Begun to coincide with renewed interest in the subject due to the release of Steven Spielberg's Close Encounters of the Third Kind. It is based on the book UFOs: Past, Present, and Future by Robert Emenegger.
From the film's Wikipedia article (CC BY-SA 4.0).