It Conquered the World (1956)

Description[from Freebase]

It Conquered the World is a 1956 American science fiction film about an alien from Venus trying to take over the world with the help of a disillusioned human scientist. It was directed by Roger Corman, written by Lou Rusoff (with uncredited contributions by Charles B. Griffith who didn't wish his name on the film), and starred Peter Graves, Lee Van Cleef, Beverly Garland, and Sally Fraser. Dr. Tom Anderson (Van Cleef), an embittered scientist, has made contact with a Venusian alien with his radio transmitter. The alien wants to take over the world using mind control devices, but claims it only wants to bring bring peace to the world by eliminating emotions. Anderson agrees to help the creature and even allows it to assimilate his wife (Garland) and friend Dr. Nelson (Graves). The alien then disrupts all electric power on Earth, including motor vehicles, leaving Dr. Nelson to resort to riding around on a bicycle. After killing a flying bat-like creature which carries the mind control device, Nelson returns home to find his wife has been assimilated. She attempts to force assimilation on him with another bat, and he ends up killing her.

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