It Came From Outer Space (1953)

Richard Carlson plays astronomer John Putnam who sees a meteor come down in the desert. Investigating, he finds an alien concealing its craft but nobody will believe him until the invaders start cloning the local townsfolk into emotionless beings. And when the aliens kidnap his girlfriend, he must use all his wits and knowldege to rescue her. This debut feature by Jack Arnold, who went on to direct This Island Earth, Tarantula and The Incredible Shrinking Man, shows his ability to use landscape as strange as the intruders - in one scene, as an alien walks across the desert, the reactions of the wildlife is enough to instil fear without any glimpse of the being itself.