Fear of the unknown is what draws audiences to the concept of hostile extraterrestrials. This is why movies like John Carpenter's The Thing and Ridley Scott's Alien are so beloved. They took the concept of a hostile alien and made it into terrifying and unforgettable cinematic thrill rides.
However, for every well-crafted hit that comes out, there are the ones that fail. The poorly made alien horror films that over-saturate the subgenre cause genuinely good films to become buried and forgotten. Among the many disappointments, there are several surprisingly great alien movies.
Good: Apollo 18 (2011)
Found footage movies were everywhere after Paranormal Activity turned the subgenre into a trend. The market was so over-saturated with them that even the good ones were too much. One of these was Apollo 18, a what-if story about the 18th Apollo mission to the moon that tells why astronauts never went back.
The atmosphere is perfect: everything is cold, quiet, and claustrophobic. The recreation of old 1960s film and technology is very well done and yes, there are aliens. What they are is a genuinely great twist and it makes for a chilling climax that is built up perfectly through the slower first and second acts.
Bad: Skyline (2010)
As an alien invasion happens, a group of people is stuck in an apartment building trying to defend themselves. Not a bad concept, and there is some creativity with the aliens themselves. Unfortunately, that's where the positives end, because Skyline is a disaster.
The characters range from bland to just annoying, the tone is all over the place, and it seems to have no idea what it wants to be. Horror, action, drama, and thriller all merged together and done poorly. The straw that breaks the camel's back though is the ending; it's so bad that it's hilarious, but somehow spawned a sequel.
Good: Signs (2002)
M. Night Shyamalan was once considered to be the new Spielberg. That view of him changed with Signs, which got a very divided response from audiences. The twist that Shyamalan brings is one that always makes or breaks the film for most. That being said, Signs is still effective as a character drama about a grief-stricken family dealing with a slowly approaching alien invasion.
The aliens themselves are terrifying, as they are kept in the shadows throughout Signs. They appear only for quick glimpses and usually effective scares. Add a great cast with Mel Gibson and Joaquin Phoenix, and there is still a lot to enjoy before the twist comes along.
Bad: Creature (1985)
A group of space travelers investigates a dark and stormy planet where they end up unearthing a parasitic alien that picks them off one by one. Sound familiar? That's because Creature is an even lower-budget ripoff of Ridley Scott's Alien. Even the titular monster itself looks almost identical to the Xenomorph.
While there are a couple of neat twists, there are too many detractions. For example, the lighting is so dark that it's impossible to tell what's happening in most scenes. Even when the creature is finally on screen, nobody can make it out. The characters are all bland and everything is obviously very cheaply made.
Good: Alien 3 Assembly Cut (1991)
The third movie in the Alien saga is the black sheep of the franchise. The version that was shown in theaters was a mess due to endless studio tampering. Even director David Fincher has openly expressed his disdain for the theatrical cut.
In 2003, a group of editors gathered as much archived footage and unaltered scenes to create a new version of Alien 3. It is a massive improvement due to subplots actually getting resolution, the pacing is better, and there are so many extra scenes that it feels like a different movie that should have been the theatrically-released version.
Bad: Alien VS Predator Requiem (2008)
From the same directors as Skyline, Alien Vs. Predator Requiem is the lowest point for the Alien franchise. The idea of returning to horror in a modern-day town might have been a good concept, but it is executed so poorly. The Brothers Strause were newcomers to filmmaking, and it shows.
Most of the movie takes place at night and sadly, the directors did not listen to the crew. Everything is way too dark to see anything, the movie goes a little too overboard with its R-rating that it feels sleazy at times, and the characters look and feel straight out of a bad Friday The 13th movie. The best thing to come out of it is the mysterious Predator known as Wolf.
Good: War Of The Worlds (2005)
The original War Of The Worlds was more of a military drama about alien invasion with too many characters to follow. The remake by Steven Spielberg takes a more centered approach by focusing on a man and his kids as they survive the attack from Martians.
Despite decent reviews and making quite a pretty penny at the box office, War Of The Worlds faded into obscurity. It's a shame because Spielberg crafted a great sci-fi thriller; the tripods, the probes, and even the aliens themselves are chilling. Tom Cruise gives one of his best performances here and the pacing is much smoother than the original.
Bad: Breach (2020)
The most recent film on this list and it is a bit of a doozy. With Bruce Willis and the criminally underrated Thomas Jane together, viewers might think Breach could be decent. Sadly no, it is a bafflingly bad alien movie that takes tropes from every other famous alien and sci-fi horror movie, but does them worse.
Breach is yet another low-budget B-movie that did not deserve the likes of Bruce Willis. It is not even in the so bad that it's funny category, it's just a bland and boring mess which is worse.
Good: Life (2017)
Here is an example of a movie that borrows from others and does it well: Life. There are elements of Alien, The Thing, The Blob, and more, but all done with a twist and a turn that helps in execution. Life also boasts a very impressive cast with Jake Gyllenhaal, Hiroyuki Sanada, Ryan Reynolds, and Rebecca Ferguson.
The claustrophobic tension is perfect, the alien itself is actually unlike other movie aliens, and the kills are very well done. Life is the best example that something doesn't have to be completely original to be good.
Bad: Dark Skies (2013)
Apparently, the filmmakers confused aliens for demons or ghosts, because that's all they are here. Dark Skies is every ghost/demon haunting movie people have seen hundreds of times. Just replace the ghosts with aliens and make it as boring as can be. It gets worse though: every member of this leading family is completely unlikable.
.Some of the scares are unintentionally hilarious, and then there are the aliens; they have only seconds of screentime and they look like a typical Hollywood alien, but always kept in the shadows and never do anything besides standing.