Invasion Of The Body Snatchers - 1956

The film's storyline concerns an extraterrestrial invasion that begins in the fictional California town of Santa Mira. Alien plant spores have fallen from space and grown into large seed pods, each one capable of producing a visually identical copy of a human. As each pod reaches full development, it assimilates the physical traits, memories, and personalities of each sleeping person placed near it until only the replacement is left; these duplicates, however, are devoid of all human emotion. Little by little, a local doctor uncovers this "quiet" invasion and attempts to stop it.