When Ridley Scott was hired to direct Alien for 20th Century Fox, he was only expected to deliver a haunted house movie in space. For all intents and purposes, he could’ve phoned in the gig. But with an impeccable sense of pacing and palpable tension, Scott made Alien a masterpiece of horror cinema that’s just as terrifying today as it was in 1979.

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The movie spawned a franchise with sequels directed by such revered filmmakers as James Cameron and David Fincher, although the studio interfered with the latter’s vision. Some Alien movies have been adored by critics, while others have been despised.

8 Aliens Vs. Predator: Requiem (12%)

Aliens vs Predator Requiem

The first Alien vs. Predator movie was nothing to brag about, but at least it kept the focus on the titular E.T.s. The sequel, Requiem, is just a banal horror movie about a bunch of walking clichés.

Following on from the tease at the end of the first movie, Requiem revolves around a hybrid of the xenomorphs and the predators known as the “Predalien.” It’s as stupid as it sounds.

7 Alien Vs. Predator (21%)

Alien vs Predator

When Fox found itself with two sci-fi action horror franchises about bloodthirsty alien species that like to kill humans, a crossover seemed like a no-brainer. The setting of an underground pyramid in the Antarctic is an interesting one, but it’s wasted.

Despite the tantalizing possibilities of the monsters from the Alien and Predator franchises battling it out, Alien vs. Predator is a painfully dull, by-the-numbers blockbuster.

6 Alien 3 (43%)

Technically, Alien 3 is the directorial debut of David Fincher. However, rather than being a calling card for the filmmaker who would go on to direct Se7en, Fight Club, and The Social Network, Alien 3 is a prime example of a disappointing threequel. Fincher has since disavowed the film, as his vision was significantly altered by pesky meddling studio executives.

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From its very opening scene, which kills off a bunch of fan-favorite characters off-screen, it’s clear that Alien 3 isn’t going to satisfy as a follow-up to Alien and Aliens.

5 Alien: Resurrection (54%)

Alien Resurrection

The first run of Alien movies had kind of run out of steam by Alien: Resurrection, which revolves around a hybrid clone of Ripley and a xenomorph soaring through space with a band of pirates.

Having such greats as Ron Perlman and Winona Ryder in supporting roles couldn’t save Resurrection from a muddled script (written by Joss Whedon) that gets lost in trying to explain Ripley’s return.

4 Alien: Covenant (65%)

Alien Covenant

After the radical changes that Prometheus made to the Alien formula, Ridley Scott went back to basics for Alien: Covenant, which sees a space crew encountering a new kind of xenomorph called a “Neomorph.” Katherine Waterston’s performance isn’t as groundbreaking or revelatory as Sigourney Weaver’s turn in the original movie, but she’s compelling enough to carry the movie.

While Covenant’s attempts to follow up on Prometheus’ mysteries fall flat, the movie really shines when it just focuses on wringing terror out of the aliens’ attack.

3 Prometheus (73%)

Prometheus

Ridley Scott returned to the Alien franchise in 2012 for a prequel that promised to explain everything. However, the movie ended up asking more questions than it answered – and it also begged the question, does the origin of the xenomorph even matter?

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Still, Prometheus is a dazzling sci-fi epic anchored by terrific performances by such actors as Noomi Rapace, Michael Fassbender, and Charlize Theron. If Scott gets to finish the Alien prequel saga, maybe all the questions will be answered and Prometheus will make a lot more sense, but as it stands, it’s a pretty confusing movie.

2 Aliens (97%)

Sigourney Weaver in Aliens

When James Cameron was hired to write a sequel to Alien, he knew he couldn’t come up with a horror movie that would top Ridley Scott’s original masterpiece, so he decided to switch genres. Aliens is an action-packed extravaganza. After facing the fight of her life against one xenomorph, Ripley suddenly has to contend with dozens of them. She’s reluctantly sent with a band of Colonial Marines to a colonized planet that’s been invaded by xenomorphs.

Ripley’s character is significantly expanded in Aliens, too, as she learns that her daughter has died while she’s been in space and she becomes attached to an orphan she finds living in the aliens’ nest. Aliens was one of two perfect sequels helmed by Cameron – a few years later, he blew audiences away again with Terminator 2’s mesmerizing action and technical innovation.

1 Alien (98%)

Harry Dean Stanton in Alien

The genius of Ridley Scott’s Alien is that it takes its time building to each scare. The iconic chestburster scene doesn’t appear until halfway through the movie, by when all the characters are well-established. By the time an alien baby rips its way out of Kane’s chest, he feels like a real person, making it all the more horrifying.

Sigourney Weaver broke new ground for female action heroes in the role of Ellen Ripley, single-handedly proving that women can be just as badass as men, while H.R. Giger’s timeless designs are hauntingly beautiful.

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