With the weak, disappointing sequels that we’ve seen so far this year at the movies — including Batman v Superman, X-Men: Apocalypse, and the abysmal Independence Day: Resurgence — it’s getting difficult to remember (or believe) that a follow-up to a successful film can actually be an improvement on the original.

Yes, I realize some of you will counter that assertion with citing The Empire Strikes Back or The Godfather: Part II as great sequels. But I would argue that those movies and other strong sequels like The Road Warrior or Star Trek II: The Wrath of Khan were continuations of a larger story, rather than another standalone film that came after a breakout hit.

(This continuation caveat applies to nearly every superhero sequel, doesn’t it? It’s essentially understood that those properties are intended to be multi-film franchises. So movies like Spider-Man 2, X2: X-Men United, The Dark Knight, and Captain America: The Winter Soldier weren’t necessarily created when their predecessors were breakout hits. Sequels were already part of the larger plan.)

The Terminator seemed like a standalone film in 1984. Arnold Schwarzenegger wasn’t yet a huge action star, with two Conan the Barbarian movies on his résumé, so this could be seen as something of a B-movie. While some make-up effects and stop-motion animation was used (neither of which hold up 30 years later), this was essentially a slasher horror flick about a robot sent from the future to assassinate someone in order to prevent a post-apocalyptic revolution from ever happening.

Naturally, the hope is for every movie to be a success. But The Terminator was a surprise hit that made stars out of Schwarzenegger and director James Cameron. Interestingly, Cameron’s next project was a sequel to another surprise hit, 1979’s Alien, that was arguably an improvement upon the original film.

More importantly, it was really a reinvention, taking  characters from one story and creating a completely different movie around them. If Alien was a horror movie, 1986’s Aliens was a heavy-hitting action flick that broadened the scope of the first story, helped create a mythology, and made a big-screen blockbuster which essentially ignited a franchise.

Five years later, Cameron did the same thing with his own creation in the sequel Terminator 2: Judgment Day. The Terminator did establish a world in which other stories could be told, particularly the dystopian future in which the machines wiped out humanity and took over the planet. But instead of branching out the mythology he created, Cameron doubled down on his original story, amping up the action, creating a far more formidable adversary and taking the villain from the first film and making him a hero.

This was the sci-fi/action movie version of a pro wrestler turning from heel to face. Yet somehow, Cameron managed to turn his fearsome, relentless killing machine into a protector. He also made Schwarzenegger’s Terminator fallible and vulnerable by pitting him (it?) against an upgraded robot with abilities never before seen on screen, thanks to some revolutionary digital effects.

It was a brilliant twist on the original story by Cameron. On the surface, Terminator 2 was set up to make the same mistakes that so many sequels to successful films previously committed. Get the band back together and just make everything bigger. Bigger action, bigger set pieces, bigger special effects.

Yet the circumstances of this story weren’t contrived. Yes, the storyline was arguably repetitive: Another robot is sent from the future to kill someone and change the future. In the first film, the target was Sarah Connor (Linda Hamilton), who will someday give birth to the future leader of the resistance of the robots. But with that mission thwarted and that son being born, the machines decide to try again, this time sending a more lethal assassin to kill John Connor (Edward Furlong) before he grows up into the man who becomes the eventual savior of humanity.

Cameron emphasizes the twist to this story by using the audience’s memory to play with its expectations. Like John and Sarah Connor — who have either been trained to flee from or remember the threatening image of a hulking man dressed in black, wearing a leather jacket and sunglasses — we as viewers see Schwarzenegger approaching and are immediately afraid of his intentions, especially when he pulls out a shotgun. But now, the big, bad robot is here to help.

At first glance, the new T-1000 (Robert Patrick) appears to be no physical match. Despite a clear expression of malicious intent, the new Terminator is smaller and leaner, and could seemingly be easily overpowered by Schwarzenegger’s more imposing T-800. But the T-1000 has much more than brawn and persistence in its arsenal. As we quickly see after taking five shots to the chest by the original Terminator, this new model shows that it’s made of liquid metal that can shift shape and reassemble after being broken.

Another twist off the original concept that Cameron takes is that Sarah Connor is no longer a victim or damsel in distress. Her encounter with near-death and awareness of the doomed future to come has made her into a hardened warrior whose life intention is to protect her son and prepare for a future war. Hamilton turned herself into a muscled action figure for the role, surely inspiring a generation of fitness freaks and CrossFit junkies to become hardbodies. This was no girl that needed to be rescued. Sarah Connor became a female action icon.

In addition to turning from the hunted into the ultimate protective mother, Connor also becomes a predator herself. Convincing herself that Judgment Day can still be prevented, she decides to kill the scientist who creates the computer network that evolves into Skynet, the artificial intelligence which becomes self-sufficient and reaches the conclusion that humans are inferior to machines.

Upon finding engineer Miles Dyson (Joe Morton), however, Connor learns the fatal reality that Cameron seemingly folded into this entire mythology: The apocalypse was always meant to happen. Dyson creates Skynet by reverse-engineering the technology that was left behind when the first Terminator attempted to kill Connor. So where does this entire story truly begin and how can it possibly end? Both John Connor and Skynet were spawned by the future intruding upon the past.

That’s not where Terminator 2 ends, but that inherent premise of inevitability fueled three subsequent sequels (and even a TV series), neither of which came close to the bar Cameron set with his sequel. (He wasn’t involved in the production of any of the other Terminator films.)

“Terminator” became a brand name that production companies and film studios tried to sell, rather than create an organic continuation of the mythology. The next movies either basically tried to tell the same narrative (2003’s Terminator 3: Rise of the Machines, 2015’s Terminator Genisys) under the facade of reinventing the core story or attempted to delve into that future war between man and machine (2009’s Terminator Salvation).

Neither of those efforts turned out to be fully compelling because the best part of the story had already been told. Cameron arguably went on to greater filmmaking heights with Titanic and Avatar. At the very least, he was smart enough to know that he couldn’t top himself with another Terminator film. Schwarzenegger has never been able to stay completely away, perhaps because he’s so closely associated with the character. But even he couldn’t save the terrible Genisys, which may have killed the franchise for good.

The tendency now is to make every franchise into a trilogy or just keep milking that brand recognition for an extra payday. But besides establishing a high standard for sci-fi and action movie sequels, Terminator 2 might be the best example of leaving on a high note and going out on top. Twenty-five years later, it’s still one of the best films of its kind.

About Ian Casselberry

Ian is a writer, editor, and podcaster. You can find his work at Awful Announcing and The Comeback. He's written for Sports Illustrated, Yahoo Sports, MLive, Bleacher Report, and SB Nation.