Michael Rennie (25 August 1909 – 10 June 1971) was an English film, television, and stage actor, perhaps best known for his 1951 starring role as the space visitor Klaatu in the 20th Century Fox classic science fiction film, The Day the Earth Stood Still. In a career spanning more than 30 years, Rennie appeared in 50-plus films and in several American television series.