Ridley Scott and Noah Hawley are currently hard at work on an Alien TV series that will take place on Earth in the future. Filming is set to begin next year, and the show will eventually premiere on FX on Hulu. The tone of the series is being compared to the first two visceral and intense entries in the franchise, which were universally praised by both critics and fans, as opposed to the more divisive and lackluster sequels and prequels that followed.

Some of the movies in the Alien franchise, like Scott’s groundbreaking 1979 original and James Cameron’s more action-oriented but equally terrifying sequel Aliens, are a lot scarier than others, like the disappointing Alien Resurrection and the straightforward sci-fi epic Prometheus.

Prometheus (2012)

Michael Fassbender holding a globe in Prometheus

In 2012, Ridley Scott returned to the Alien franchise with the big-budget prequel movie Prometheus. While some Alien fans questioned the necessity of a film filling in the franchise’s lore and explaining the backstory of the xenomorph race, Prometheus is an undeniably beautiful movie. But since it’s more of a straightforward science fiction movie than a horror movie, the film isn’t as scary as its predecessors.

Still, Prometheus has a couple of spooky moments. The Engineers have a haunting on-screen presence. When Elizabeth Shaw discovers an otherworldly being growing inside her, she performs a gruesome self-inflicted surgical procedure to remove it. This sequence might not be as iconic as the original film’s chestburster scene, but it’s just as difficult to stomach.

Alien Resurrection (1997)

Ripley and the rest of the crew submerged in water in Alien Resurrection

Jean-Pierre Jeunet’s fourth entry in the Alien franchise, Alien Resurrection, received almost universally negative reviews. The movie gets too bogged down in the sci-fi lore of bringing Ripley back to life to succeed as a horror film. There is one truly creepy moment that stems from this cloning storyline as Ripley stumbles upon a bunch of failed attempts to clone her, but it’s still nothing compared to the scariest moments from the franchise’s first couple of installments.

There’s also a great underwater set-piece that translates the terror of a space monster into the murky watery depths, but Resurrection is a mostly scare-free installment in an iconic horror franchise that deserves a lot better.

Alien 3 (1992)

Ripley is confronted by a xenomorph in Alien 3

In Alien 3, David Fincher’s directorial debut, Ripley finds herself stranded on a prison planet full of convicts so nefarious that they couldn’t even be trusted behind bars on Earth. Naturally, the alien killers quickly show up to terrorize this planet, but Ripley is surrounded by monsters long before the xenomorph returns. After the near-flawless initial two movies, Alien 3 was the first entry in the franchise to be met with a mixed critical response.

It’s a serviceable sci-fi thriller, but it pales in comparison to the previous two movies. Alien 3’s dog-like “Dragon” xenomorph is an interesting twist on the familiar alien design, but it looks too silly to strike the same fear into audiences that the usual seven-foot menace does.

Alien: Covenant (2017)

A xenomorph latches onto a ship in Alien Covenant

After the mixed response to Prometheus, Scott returned to the series’ horror roots with Alien: Covenant. Katherine Waterston takes Sigourney Weaver’s place as the badass “final girl” who goes head-to-head with the titular star-beast in the finale. Like the 1979 original, Covenant is a haunted house movie set in space. It takes longer to get there than the original movie, but it ends up with a xenomorph running loose on a space station, brutally picking off the crew members one by one.

Scott shows much less restraint with the gore this time around than he did in the meticulously crafted original movie. But this unrestrained gore leads to plenty of frightful moments: a dust-based alien parasite settles in an unsuspecting astronaut’s ear canal; a xenomorph rips two lovers to shreds in the middle of an amorous love-making session in the shower.

Aliens (1986)

A xenomorph rises up behind Newt in Aliens

James Cameron’s Aliens, the acclaimed sequel that pluralizes the eponymous monster and ramps up the thrills, is more action-oriented than its predecessor. It’s often called an action movie as opposed to a horror movie, with plenty of the explosions and shootouts that are typically associated with the action genre. It’s also a heartwarming mother-daughter story, as Ripley takes a young orphan named Newt under her wing after learning that her own daughter has died of old age back on Earth.

But despite its spectacular action sequences and moving maternal narrative, Aliens still has its fair share of bone-chilling horror set-pieces, from Hicks poking his head into the ceiling vents and seeing a swarm of bloodthirsty xenomorphs ominously advancing toward him to Burke releasing a facehugger in the room where Ripley and Newt are taking a nap.

Alien (1979)

Brett is confronted by a xenomorph in Alien

The Alien franchise has yet to top the original work. Scott was hired by 20th Century Fox to helm a standard B-movie, but he ended up turning out one of the most terrifying horror movies ever made. In his timeless 1979 masterpiece, Scott expertly builds the tension throughout the first half before unleashing the xenomorph on the Nostromo for a relentless bloodbath in the second half. Jerry Goldsmith’s mesmerizing score and H.R. Giger’s unsettling production design immerse viewers in the creepy world of the film, while screenwriter Dan O’Bannon’s no-nonsense storytelling doesn’t give the audience a second to back away from the edge of their seats.

From the initial attack by the facehugger to Dallas illuminating the xenomorph in a dark tunnel, the original Alien movie is full of fiercely effective jump scares. The chestburster sequence is one of the most iconic moments in the entire history of horror cinema.

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