Aliens set a tough standard for subsequent installments of the Alien franchise to match, and a few things help explain why. The first two movies in the Alien sci-fi movie series couldn't be more different, yet 1979's Alien and its 1986 sequel, Aliens, receive equal love from fans of the franchise. Despite its seminal place in both horror and sci-fi, the Alien franchise is often seen as having peaked with Aliens.

To be fair, both Alien and Aliens are classics on such a level that following up on them was always going to be a challenge. Sigourney Weaver's iconic performance as Ellen Ripley and the directorial talents of first Ridley Scott and then James Cameron cemented the two movies into the public consciousness forever. In the grand scheme of the Alien franchise, any installment being ranked a step or two below Alien and Aliens almost goes without saying.

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Still, even with the heights reached by Aliens and the complete franchise re-invention it represented, the Alien film series has largely struggled to attain comparable reception since. With Alien 5 officially in the works with Fede Álvarez directing, along with an Alien TV series in development, the Alien franchise hasn't faltered despite its post-Aliens reception. Still, it's challenges in the intervening years have largely boiled down to creative decisions that failed to connect with audiences. Here are the major reasons why the Alien franchise hasn't managed to equal the standards set by Aliens.

Alien 3 Started A Trend With The Franchise's Characters

The alien approaches Ellen Ripley in Alien 3

Alien 3 began with what is still one of the most infamous sci-fi movie openings of all time with the death of Aliens characters Hicks (Michael Biehn) and Newt (Carrie Henn). With Alien 3 picking up right where Aliens left off, the movie's opening shocked audiences with how much it undercut Hicks and Newt's survival and their bond with Ripley. Alien 3 writer Vincent Ward has said this was done partly to have Ripley deal with tragedy in the follow-up, but this lost the movie a lot of audience goodwill right from the startMoreover, its setting on a prison planet full of killers and rapists left viewers with the Xenomorph pursuing characters they had no emotional investment in.

In doing this, Alien 3 started a downward trend in the franchise of having characters in subsequent movies being much less engaging than those of Alien and Aliens. Ridley Scott's Alien prequel movies, Prometheus and Alien: Covenant, had break-out characters in Michael Fassbender's androids, David and Walter. Still, these movies had their own issue of being centered on scientists making consistently foolish choices that inevitably lead to their demise. The first two Alien movies do the best job of any in the series of getting audiences to become attached to their human characters. From the extremely dark approach of Alien 3 on, characters who weren't Ripley easily fell into the trap of being canon fodder.

Aliens' Space Marines Are Hard To Beat

Colonial Marines in Aliens

When it comes to characters, Aliens also set a whole new tone for the Alien franchise with its introduction of the Colonial Marines. After communication with the human colony on LV-426 is lost, these space marines are deployed to the terraformed planet with Ripley along for the ride as an advisor. This provides Aliens with a huge tonal shift from the slow-drip horror of Alien to become a heart-racing action movie. Cameron's direction made the transition feel perfectly natural, while the space marines set the bar for the Alien franchise in a whole new way.

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No subsequent Alien movie has involved space marines, and the popularity of Aliens shows how hard they've been to move on from. As a unit, they're a great concept for a sci-fi movie set on another planet that was also an allegory for the Vietnam War. With Colonial Marines like Michael Biehn's Corporal Dwayne Hicks, Vasquez (Jeanette Goldstein), Hudson (Bill Paxton), and several others, audiences have many strong individual characters to latch onto. Hudson, in particular, helped Aliens to become the most quoted entry in the Alien series with his "Game Over, man!" meltdown. The space marines of Aliens have long loomed over the series ever since. With subsequent Alien movies focused on smugglers, scientists, and human civilians, the franchise has never managed to find anything that resonates with audiences the way the space marines in Aliens do.

The Alien Franchise Hasn't Added Much New Material

Xenomorph in Alien Covenant

Aside from losing much of what made it popular to begin with, the Alien movies haven't added much new to make up for it. Alien 3 went in an unexpected direction with Ripley becoming pregnant with a Xenomorph queen and sacrificing herself in order to kill it. However, Ripley was cloned in Alien: Resurrection and brought back into the game 200 years later. Both movies, in many ways, still delivered more of the same, with humans mainly being chased and decimated by their Xenomorph pursuer. Alien 3 especially had an infamously troubled pre-production phase. The makers of Alien 3 dropped numerous ideas, like space monks, a more central role for Hicks, and the set-up for a huge war in the fourth film. Looking back, these were concepts with great potential — though the monks idea was somewhat retained with Alien 3's celibate inmates.

Post-Aliens, the franchise has continually inched back towards humans fleeing in terror from Xenomorphs in one scenario or another. Prometheus started the franchise on a new path, but aside from altering the villainous arc of David, the movies just brought back the concept of Xenomorphs chasing humans with its sequel, Alien: Covenant. The Alien vs Predator movies delivered the crossover that fans had waited years for, since the Xenomorph skull tease in Predator 2. However, neither installment lived up to the idea. Post-Aliens, it seems the major struggles the Alien franchise has dealt with are the lack of fresh ideas and the new concepts with potential not catching on. Compared to Aliens' continued popularity with additions like space marines and the idea of the Xenomorph queen giving a look into the species' society, the Alien franchise installments that have come about since have had a tough time measuring up to it.

With one of the most terrifying and enduring monsters in cinema history, Alien used the Xenomorph and the setting it was in to create a claustrophobic horror movie in the depths of space. Aliens later made the leap to an action movie without any tonal whiplash, and both movies had a strong cast of characters led by Sigourney Weaver's Ripley, along with other clever ideas in their repertoire. The first two installments show the inherent malleability of the Alien franchise that's built into the series plus the different kinds of territory it can venture into. The Alien franchise has unfortunately been unable to hit the same mark that Aliens left the series at back in 1986, but hopefully, the upcoming entries can succeed in that endeavor.

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