Add Yahoo as a preferred source to see more of our stories on Google. Some of the greatest sci-fi movies of all time revolve around humans in a desperate struggle for survival. Sometimes we’re ...

For your extraterrestrial viewing needs, Stacker ranked the top 30 alien movies, according to their IMDb user rating.

Spielberg has graced the silver screen with countless creative alien species in his career, and some have shown to be more threatening than others.