When it comes to the best sci-fi franchises out there, they all have one very big thing in common. They all have very memorable villains and very memorable heroes. The best of the best really can't have just one or the other. The best movies need to make sure and have both in order to play off one another. Of course, even when a movie has a good guy and a bad guy, there isn't a guarantee that the characters in that sci-fi movie are going to be memorable for generations. That's why there are so few heroes from these movies that really stand the test of time.

There's a certain trait that heroes that really "stand the test of time" need to have. It's those traits that also allow the love of those characters to go from one generation to another. Whether talking about the Star Wars franchise, or Star Trek or any other of the big science fiction IPs out there, the heroes need to be able to stand out from the pack of heroes that are already in those movies. These particular franchises have plenty of protagonists. There's a reason why these heroes are the most popular of the entire group. There's a reason why with the literally hundreds of different science-fiction franchises these five are at the top of the heap.

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Mr. Spock

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There's a reason why the phrase "live long and prosper" is even known by people that aren't necessarily science-fiction fans. In fact, it's a safe bet that while people might have heard that phrase before, some might not even know why they know it. The reason that Mr. Spock stands out from the many, many heroes that are involved in the Star Trek franchise goes beyond "live long and prosper." It's the fact that he led a life that others could aspire to and it wasn't because he was someone who was just "cool." There was another phrase that Spock is well known for and that led to ... one of his deaths. "The needs of the many outweigh the needs of the few."

Mr. Spock was certainly accompanied by other memorable science-fiction heroes. James T. Kirk, Dr. McCoy, and even Scott are almost as popular. There's a reason why the Star Trek franchise is still going even though it's being carried by new versions of the classic characters. But while those characters are well known and well-loved, Spock is the one that people who aren't even followers of the genre know and quote.

Doctor Who

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While Doctor Who has mostly been on TV, the character has also had plenty of movie-length specials that they have allowed them to set themselves apart. In fact, there may not be a character on the list that more embodies the idea of "standing the test of time" considering the large group of people that have taken on the mantle of Doctor Who.

Like Mr. Spock, it's mostly been the moral compass of Doctor Who that makes them so popular, no matter what actor or actress is playing the part. No matter who has appeared onscreen as The Doctor they have taken a hard line against hurting people if they can help it. Even when it comes to those that viewers might think deserve to be hurt. The fact that the character continues, through one generation to another, means Doctor Who truly does stand the test of time.

Ellen Ripley

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While Doctor Who is finally being played by a woman, Jodie Whitaker is part of a bigger picture. That particular character isn't known as a woman but rather had a woman take on the role during its run. The same can't be said for Ellen Ripley. Sigourney Weaver made the Aliens character what she is today and she did it by showing a real evolution through several different films. In the very first Alien, she was little more than a bystander as a massive, evil creature took out the people all around her. Over the course of several other movies, she got stronger and more sure of herself and how to deal with the creatures. Eventually she even turned into a bit of an action-hero/killing machine.

During this particular evolution she showed that women characters in science fiction movies like Aliens don't have to be any kind of "damsel I distress." They don't have to be an afterthought. Considering Ellen Ripley made her first appearance in 1979, that was not, in any way shape or form an established fact. It's not almost four decades later and much like Mr. Spock, or Doctor Who, people who aren't even sci-fi fans have likely at least heard the name Ellen Ripley, even if they don't know who she is or why they know the name.

Optimus Prime

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The only non-human on this list makes it because he might be a robot, but Optimus Prime is a robot with a heart of gold. While he made his first appearances as an animated character in a children's cartoon, he's grown into much more than that, thanks in part because he's always been someone who wanted to do the right thing and put the concerns of innocents over his own. The character is one that kids who watched the shows and then eventually watched the animated movie looked up to.

He's also the character that is popular enough and loved enough that he spawned a live-action franchise as well. That's allowed Optimus Prime to live on much longer than anyone thought he would. While that live-action version might not be getting the same cache as the original, it's clear that the character has stood the test of time and will continue to be beloved and talked about for years and generations to come.

Darth Vader

darth vader

Yes, it's true that most people would consider Darth Vader one of the quintessential baddies in sci-fi, but those people forget that while the man did some truly horrendous things, but he also took a turn at the very end of the first trilogy in the ever-growing Star Wars franchise. It's safe to say that if Darth Vader hadn't eventually picked the side of his son, rather than the emperor, things could have turned out very, very different for the rebellion.

If Darth wasn't a hero for the most part of his existence in those first three movies, he was a hero for a minute and it was a big minute. There's also very little doubt that the character stands the test of time. His very characteristic breathing is something someone can identify quite quickly, the same way horror fans can pinpoint the music from Halloween.

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