List of the best extra-terrestrial and alien films ever made. Aliens remain one of the most persistent subjects for films, particularly in the horror and sci-fi genres. Though movie aliens take on a variety of different forms, powers and appearances, they are almost always depicted as inscrutable subjects of fascination for human characters, often leading to debates about their true purpose for visiting Earth and contacting humanity.
The majority of movies about aliens depict them as villains, displaying violent aggressive behavior and, often, with plots in mind to colonize the Earth or steal our valuable natural resources. H.G. Wells classic novel "War of the Worlds" (itself adapted numerous times for the screen) established the pattern of these stories: Aliens arrive on Earth, at first humans are uncertain how to react to them, and then an attack commences that the world's citizens must band together in order to prevent. ("Independence Day" is perhaps the modern example of a film sticking closest to this format, but movies as diverse as "Invasion of the Body Snatchers," "They Live" and even "The Day the Earth Stood Still" continue to stick relatively close to this basic model.) Many of these films, and indeed much of the science-fiction genre more generally, look to the possible human failings that led to a violent conflict, providing an opportunity for social commentary and even satire alongside the more recognizable genre elements. Oscar nominee "District 9" provides a clear example of a film using a traditional "genre" alien plot to look deeper at the controversial immigration issue.This list contains the best alien and extra-terrestrial films ever made, from genres including comedy, drama, science-fiction, thriller and horror. Be sure to vote your favorites up to the top, and if you see a film that should be on here and isn't, add it below!