UFO was live action SciFi show from the puppet master himself, Gerry Andersen, that ran for a single season of 23 episodes back in 1970.
Great actors, dark thoughtful scripts that always didn’t have a happy ending, sharp miniature work, and a late 60s sense of style and fashion made this show really stand out. Oh and the purple haired moon chicks in silver miniskirts. The cast included Michael Billington, who, according his wikipedia entry, was screen tested for the role of James Bond more than any other actor.
The show also other cool eye candy, including the gull wing door cars, nuclear submarines with a jet fighter mounted on their bow, space interceptors and S.I.D. (Space Intruder Detector). What really made the show was the dark, thought provoking scripts, complex characters and some fine acting by Billington, Ed Biship and Gabrielle Drake.
There is a UFO movie, based on the series in the works. Currently scheduled for a Summer 2013 release.