Alien life forms

Main article: Extraterrestrial life in popular culture

The concept of life, particularly intelligent life, having an extraterrestrial origin is a popular staple of science fiction films. Early films often used alien life forms as a threat or peril to the human race, where the invaders were frequently fictional representations of actual military or political threats on Earth. Later some aliens were represented as benign and even beneficial in nature in such films as Escape to Witch Mountain, Return from Witch Mountain, Race to Witch Mountain, The Cat from Outer Space, E.T. the Extra-Terrestrial, Lifted and Close Encounters of the Third Kind. Aliens in contemporary films are still often depicted as hostile, however, such as those in the Alien series of films.

In order to provide subject matter to which audiences can relate, the large majority of intelligent alien races presented in films have an anthropomorphic nature, possessing human emotions and motivations. Often they will embody a particular human stereotype, such as the barbaric warriors, scientific intellectuals, or priests and clerics. They will frequently appear to be nearly human in physical appearance, and communicate in a common Earth tongue, with little trace of an accent. Very few films have tried to represent intelligent aliens as something utterly different from human kind (e.g. Solaris, Contact).