The thing about sci-fi movies is that they tend to age rather quickly. What was great special effects a few years ago quickly loses its luster with the next round of CGI updates. And movies based on theoretical hard science is often disproven soon after the movie is made (if it was, in fact, correct at the time the movie was made).

So in order to endure for nearly 60 years, a sci-fi movie has to have something else: the core of an idea that grabs hold of your brain and won't let go. Here are ten of those movies from the 50s that still have the power to blow your mind.

10 Invasion Of The Body Snatchers


Invasion of the Body Snatchers goes at the bottom of this list because people are jaded to the basic premise and concept, even though most haven't seen the original masterpiece (or even the equally-good 70s remake). But the way the movie explores the concept is chilling to this day.

At the early stages of the invasion, the people who come forward seem truly hysterical because they are gripped by a deep existential terror, even when their fears should be relieved. A woman's terror at discovering the impostor actually has what she thought was an identifying scar sends shivers down the spine.

9 The Day The Earth Stood Still


Another movie that has been somewhat diminished by a lackluster sequel, The Day the Earth Stood Still captures Cold War paranoia perhaps better than any other film. People are so highly suspicious "John Carpenter," a man who has so obviously come in peace. The images of people sitting around their television sets, ignorantly taking in limited diet of news that's parceled out will make one grateful of the Internet, despite its faults and misinformation.

It might seem hard to believe that his overtly protective gesture would get Mr. Carpenter killed, but think what fear can make people do to innocents today.

8 The Crawling Eye


The Crawling Eye is a creature feature that packs a surprising wallop. Between the strange and brutal deaths on the mountain, the psychic tie-ins, and the overt threats to children who you aren't sure are going to make it, this movie hits hard for its day.

It is lacking somewhat in social critique, but if you don't find that the story really grips you as it has many viewers, you will still be amused by the effects, which range from compelling to hilarious, but are truly unique in all of sci-fi, and may just have inspired the beholder.

7 It Came From Outer Space


Speaking of monocular aliens, a much better production is this Ray-Bradbury-penned alien invasion flick. The movie does a great job of building some heady suspense with judicious use of "monstervision," a creepy soundtrack, and a host of weird happenings. And the monsters, when we see them, are truly alien, and look as if they're decades ahead of their time with the quality of effects.

For an early sci-fi movie, this one defies a lot of conventions and has a surprising turn at the end. Oh, and you'll get to see stars from Gilligan's Island and The Creature from the Black Lagoon, as well as another film on this list too!