In 1951, Michael Rennie was Klaatu, an alien ambassador to Earth, who brought an ultimatum for Earth's governments and scientists. If they could not stop their violent ways, they would face annihilation by the cosmic Peacekeepers represented by Gort, the giant robot.

In 1967 and 1968 Quinn-Martin productions aired a show about an architect (Roy Thinnes) who sees an alien spacecraft land in a lonely field and tries to tell the world about it but is thwarted repeatedly.

In Season 1, Episode 10, (The Innocents), an alien (played by Michael Rennie) tries to brainwash him that all is well and the aliens mean no harm. For fans of the 1951 movie, this appearance is either funny or spooky.

Rennie, (25 August 1909 – 10 June 1971) was a British film, television and stage actor, perhaps best remembered for his starring role as the space visitor Klaatu in the science fiction film The Day the Earth Stood Still (1951). In a career spanning more than 30 years, Rennie appeared in more than 50 films and in several American television series.

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