It Came from Outer Space

A 1953 Science Fiction film best known for subverting some of the typical Alien Invasion tropes. Based on a script by noted SF author Ray Bradbury, its title has become part of popular culture though the film itself is more obscure.

Set in the Arizona desert, the movie begins with a meteor-like object crashing near a small town. A local scientist named John Putman and his girlfriend investigate, thinking it's a UFO, but find no evidence of it.

However, the audience sees something watching them and other people (though not exactly what -- we are shown things from the "monster's" alien viewpoint). People from the town start to get captured and replaced with emotionless doubles. The protagonist notices but cannot convince the other townsfolk of it at first; eventually he confronts one of the aliens, who reveals that... they have crashed on Earth by accident, and just want to repair their spaceship and leave. Knowing the humans would be repulsed by their true appearance, they were forced to act secretly to obtain the materials they need. The alien proves his point by revealing its true form to the hero, who indeed recoils in horror.

Eventually, the local sheriff becomes convinced that the alien 'invasion' is real, and gathers a posse to attack the aliens in their hiding place (a mine). One of the aliens is apparently killed before Putman can straighten things out. Fortunately, the aliens don't retaliate, instead returning all the replaced people (including the hero's girlfriend) unharmed, and then they take off back into space in their by-now fixed spaceship, with the Aesop of 'not fearing that which is different' having (hopefully) been learned by the cast.

The movie's use of a "fishbowl lens" camera (for the aliens' viewpoint scenes), creepy music, and foreboding desert vistas help sustain its atmosphere of suspense.

The movie had a remake in the 80s, with a different cast and alien designs, but basically the same story (except that .)

The title of the movie is often referenced or parodied, as can be seen even here in TV Tropes.

Trope examples:

 * Alien Abduction: Humans are kidnapped both as hostages and to copy their bodies. Unfortunately hearing your former friend say in a Creepy Monotone that he means you no harm is not reassuring to most people.
 * Alien Among Us
 * Alien Invasion: Inverted.
 * Beauty Equals Goodness: Inverted
 * Blob Monster
 * Came From the Sky: A meteor-like object crashing near a small town, John and his girlfriend go to investigate.
 * Coming in Hot: The pre-credit sequence has the alien spacecraft (with sparks flying off it) crashlanding in the Arizona desert.
 * Death Ray: Putman is shocked to find the aliens assembling what appears to be a classic giant Death Ray, but it's actually a device for powering their ship. Minutes before however Putman was nearly killed by a hostile alien guard with a Disintegrator Ray, so he has good reason to be worried.
 * Every Car Is a Pinto: When Fake Frank crashes his truck, it explodes.
 * Exactly What It Says On the Tin: The title
 * Oculothorax: The Aliens.
 * Voluntary Shapeshifting: The aliens can copy humans and their memories, but give themselves away through their awkward speech patterns and ability to stare into the sun without blinking.
 * We Come in Peace, Shoot To Kill: Played out on a small scale with the sheriff who wants to go in with a posse and the amateur astronomer who's willing to trust that the aliens are telling the truth. However the trope is subverted on both sides -- humans and aliens are portrayed as fearful and suspicious of each other, yet in reality both are reasonable. The locals just want their friends (who are being held hostage) returned unharmed, while the aliens just want to repair their spaceship and leave without trouble.
 * What Happened to The Mouse?: In the sequel, a coyote is duplicated as well. This is not addressed by the end.