After his breakout hit Jaws gave him the freedom to make whatever movie he wanted, Steven Spielberg decided to explore a subject that had always fascinated him: the possibility of extra-terrestrials coming to Earth. He would later cover the same topic in E.T., War of the Worlds, and Indiana Jones and the Kingdom of the Crystal Skull, but Close Encounters of the Third Kind remains his greatest study of alien life.

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Most movies about aliens coming to Earth involve an attempted invasion of the planet with spaceships blowing up skyscrapers and humans being slaughtered en masse. But some are more cerebral and thought-provoking, like Close Encounters.

Close Encounters Of The Third Kind (1977)

Barry standing in the doorway in Close Encounters of the Third Kind

Steven Spielberg had wanted to make a movie about UFOs for a while and finally hammered out an idea for Close Encounters of the Third Kind when he connected extra-terrestrial visitors to the paranoia surrounding the Watergate scandal and made it a government cover-up story.

The movie expertly builds to its stunning finale, which sees humans making first contact with aliens via sound and color, and engaging in an exchange program.

District 9 (2009)

District 9

After Neill Blomkamp and Peter Jackson’s film adaptation of the Halo games fell through, Jackson secured Blomkamp a $30 million budget to make an original sci-fi movie based on his own script with almost full creative control.

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Blomkamp adapted his short Alive in Joburg into the feature-length District 9, a documentary-style film about alien visitors in South Africa that serves as a powerful allegory for apartheid, of which the director has vivid childhood memories.

They Live (1988)

Nada sees aliens through his glasses in They Live

Roddy Piper stars as a drifter named John Nada who finds a pair of sunglasses that allow him to see the world as it really is in They Live. Suddenly, he’s able to see phrases like “OBEY,” and “CONSUME,” on billboards around the city.

John Carpenter’s sci-fi actioner is a sharp satire of the onslaught of capitalism, but it’s also a ton of fun. It’s the originator of this classic one-liner: “I have come here to chew bubblegum and kick ass. And I’m all out of bubblegum.”

The Wild Blue Yonder (2005)

Brad Dourif in The Wild Blue Yonder

Werner Herzog reaffirmed his command of the cinematic form with The Wild Blue Yonder, a quirky film that intersperses the narrative with footage from a real space mission.

Brad Dourif gives one of his all-time finest performances as an alien whose species tried and failed to colonize Earth, intercut with humanity’s search for a new home.

Under The Skin (2013)

Scarlett Johansson in a car in Under The Skin

Scarlett Johansson plays an alien who has taken the form of a beautiful woman to lure unsuspecting men into her trap in Under the Skin. When she gets her victims back to her home, they sink into the floor and get painfully folded into oblivion.

The movie’s portrayal of an alien’s perspective on humanity as an outsider is very poignant, particularly in one sequence as she observes a tragedy.

Invasion Of The Body Snatchers (1956)

A man and a woman run down a street in Invasion of the Body Snatchers.

When Dr. Miles Bennell’s patients all come to him with the same complaints about their closest friends acting strangely and exhibiting no emotions, he uncovers a terrifying alien conspiracy.

Arriving in the mid-1950s, critics noted strong parallels between Don Siegel’s Invasion of the Body Snatchers and America’s response to McCarthyism. Other critics noticed similarities with the then-looming threat of communism courtesy of the Soviet Union.

Alien (1979)

Alien 1979 Ellen Ripley Xenomorph Fog Ending

As a director-for-hire tasked with making a haunted house movie set in space, Ridley Scott could’ve easily phoned in Alien and taken an easy payday. But he instead used the movie’s simplistic premise to execute a masterclass in tension that’s now remembered as one of the greatest horror films ever made.

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Like any great monster movie, Alien can be read in a bunch of different ways, with the xenomorph representing different things for different people. It was designed as a metaphor for sexual assault to help non-survivors understand the trauma that comes with it.

Arrival (2016)

Amy Adams in Arrival (2016)

When aliens arrive on Earth and peacefully hover above a handful of random sites, a lingual expert played by Amy Adams is tasked with translating the ETs’ curious symbolic language in Denis Villeneuve’s Arrival, adapted from the short story “Story of Your Life.”

Villeneuve’s movie is one of the most poignant, heartbreaking gems ever made. The director expertly builds to a truly emotional ending that touches on what it means to be human.

The Thing (1982)

A scared MacReady looking at someone through some smoke

Another offering from John Carpenter, The Thing is a remake of The Thing from Another World that, along with Ridley Scott’s Blade Runner, was blown out of the box office water by E.T. in 1982 and has since been recognized as a cult classic.

RELATED: Why The Thing Is John Carpenter's Best Movie (& Why Halloween Is A Close Second)

Kurt Russell leads a cast of scientists in an outpost in Antarctica that gets infiltrated by an alien entity that can take the form of anything or anyone — including them.

2001: A Space Odyssey (1968)

2001 A Space Odyssey

Stanley Kubrick set out to make the greatest science fiction movie of all time when he collaborated with legendary author Arthur C. Clarke on the story for 2001: A Space Odyssey, and he arguably succeeded.

There are a lot of ideas at play in 2001, like the dangers of artificial intelligence, but it’s primarily about aliens using cosmic artifacts known as Monoliths to kickstart the next stage of human evolution by sending Dave Bowman on a trippy journey across the stars to Jupiter, where he becomes a Star Child.

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