The Scariest Aliens Ever from Sci-Fi Films

Fire in the Sky Aliens


Most of the alien action in this story takes place by flashback, when one of the main characters is abducted, returns home and then suddenly remembers what he experienced. The aliens trap humans inside cocoons, dissecting humans while they are still alive – all in the name of scientific experimentation. The main character himself endures brutal experiments until he loses consciousness. Worse, people at home don't believe him.

NEXT: "The Thing"

John Carpenter's The Thing


When we first watched "The Thing From Another World" (from 1951) about an alien found in the ice, we thought: "Aww, how quaint." Then John Carpenter remade it into "The Thing" in 1982 to horrify us all. In the film, the crew of an Antarctic research base mistakenly takes in an alien being disguised as a dog and it quickly mutates to impersonate crewmembers, bite off arms and sprout legs from a human head to scamper away (which still haunts us to this day).

NEXT: Predator!


Twentieth Century Fox

Since its debut in 1987, the aliens of "Predator" have fascinated and terrified audiences. In the original, Arnold Schwarzenegger takes on his typical film role of rescuing hostages in a remote area. But there's a twist. He needs to fight against a creature that the locals call "the demon who makes trophies of men." The creatures catch humans through sensing infrared and prefers targeting people with weapons, since it's more challenging. The series spawned two sequels and a third sequel, "The Predator", is expected in September 2018.

NEXT: "Alien" Xenomorph

"Alien" Xenomorph

Twentieth Century Fox

They say in space, no one can hear you scream, but I'm pretty sure even Ridley Scott heard me screech when I first saw "Alien." Then came "Aliens" and the xenomorph queen took raised the bar to a new level. With acid for blood, razor sharp claws and a piston-action bite, the H.R. Giger-designed "Alien" xenomorph is an icon of alien horror that has persisted over the decades since it Sigourney Weaver's Ripley first faced off against the creature in 1979.

FINALLY: Miss your favorite scary alien?

Who Was Scariest?

Whew! That was A LOT of aliens. So what do you think? Did these aliens make your scare list, or are them lame-o extraterrestrials? Let us know in the comments below!

This story was inspired by Episode 3 of "AMC Visionaries: James Cameron's Story of Science Fiction," which airs tonight at 10 p.m. EDT/PDT (9 p.m. CDT). A companion book is available on

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at:

Elizabeth Howell
Staff Writer, Spaceflight

Elizabeth Howell (she/her), Ph.D., is a staff writer in the spaceflight channel since 2022 covering diversity, education and gaming as well. She was contributing writer for for 10 years before joining full-time. Elizabeth's reporting includes multiple exclusives with the White House and Office of the Vice-President of the United States, an exclusive conversation with aspiring space tourist (and NSYNC bassist) Lance Bass, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, flying parabolic, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, "Why Am I Taller?", is co-written with astronaut Dave Williams. Elizabeth holds a Ph.D. and M.Sc. in Space Studies from the University of North Dakota, a Bachelor of Journalism from Canada's Carleton University and a Bachelor of History from Canada's Athabasca University. Elizabeth is also a post-secondary instructor in communications and science at several institutions since 2015; her experience includes developing and teaching an astronomy course at Canada's Algonquin College (with Indigenous content as well) to more than 1,000 students since 2020. Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. Mastodon: