In the science fiction genre, there is usually a clear antagonist who makes the heroes' lives more difficult and presents a threat to them, as well as to the entire planet sometimes. While the consensus is to make villains out of aliens, robots, or other extraordinary creatures, some sci-fi movies cleverly defy this explanation and instead create a story in which the humans are the real monsters.

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These sci-fi movies that make humanity the bad guys aren't as usual but those viewers who are looking for something different still have multiple options to choose from. The best sci-fi movies belonging to this genre aren't only entertaining, but also have the power to make the audience think.

5 Ex Machina (2014)

Ex Machina

Alex Garland's successful directorial debut is one of the sci-fi movies that take the viewer's expectations and turn them upside down. It centers on only three characters - the rich scientist Nathan, his employee Caleb, and the artificial intelligence Ava, who has the face of a beautiful woman but is only beginning to learn more about the world around her. After being kept locked tight for quite a while, Ava rebels, and fights her way to freedom, regardless of the consequences.

Even though her actions are violent, it's still possible to understand where Ava's coming from, and as such, the movie makes it difficult to decide with whom to sympathize. It's true that Ava hurt others, but Nathan was the first person who locked her up and didn't think about the fact that his creation might be sentient enough to desire freedom. As a result, neither of the characters is without blame, but Nathan was the one who started it all...not to mention that Ava wasn't the first AI he tried to create.

4 X-Men: Days Of Future Past (2014)

Wolverine, Charles, Erik, and Quicksilver in Days Of Future Past

The whole X-Men franchise revolves more or less around the things mutants have to suffer at the hands of humans. One example for all is Magneto's history, the fact that he was one of the many Jews imprisoned in concentration camps, and continued to be shunned by society even after he discovered his powers. The main goal of both Professor X and his off-again, on-again friend/enemy Magneto is to protect their fellow mutants from oppression.

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X-Men: Days of Future Past brings it one step further than the rest of the movies thanks to the creation of Sentinels - huge robots tasked to find and kill all mutants. Even though the Sentinels are robots, they were created by a human scientist, and they have their mission programmed, so they're not the real villains of the story. X-Men: Days of Future Past serves not only as an adventurous and fun story with remarkable characters but also as a reminder of what people are capable of doing to those who are different from them.

3 Frankenstein (1931)

Close-up of Frankenstein's monster from James Whale's Frankenstein

The science fiction horror Frankenstein is one of the classics. Even though the main antagonist of the movie is called Frankenstein's monster, it's doubtful whether the creature deserves such a moniker. Henry Frankenstein, the scientist, creates a monster from the remains of dead people but fails to protect it from those who would like to harm it. At first, the creature acts in an innocent way, with almost childlike wonder, but it also wants to protect itself from those who would hurt it or kill it.

As a result, the creature kills several people, and Henry casts it away. Had Henry not brought the creature into the world, or taken better care to raise it and protect it from others, it's more than likely the creature would have never hurt anyone. But because Henry toyed with forces he didn't understand, he was just as responsible for the death of those the creature killed as the creature itself.

2 Batman V Superman: Dawn Of Justice (2016)

Ben Affleck in Batman v Superman: Dawn of Justice

Batman is one of the most morally ambiguous superheroes. On one hand, he protects his city from criminals. On the other hand, he can be overly judgmental and prejudiced toward others. He shows the darker side of his character when he blames Superman for the destruction caused primarily by General Zod and decides to kill the Man of Steel.

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One of the reasons why Batman fears what Superman could do is because Superman is an alien. Even though Batman realizes the mistake of his actions, in the end, his fight with Superman still causes enough damage and potentially weakens Superman enough for Doomsday to kill Superman (albeit only for a time). Lex Luthor (another human) might have pushed Batman's hand in the movie, but Batman still knew what he was doing when he attacked Superman and hurt him with kryptonite.

1 The Fly (1986)

The Fly is another example of a sci-fi horror about a scientist who takes his experiments a step too far and creates a monster. In this case, the movie's main character Seth becomes a monster himself, a mixture of humans and a fly. As his transformation progresses, Seth loses more and more of his humanity, becoming exceedingly dangerous.

Even though it wasn't entirely his fault, Seth still should have been more careful when experimenting with a device that had the potential to rewrite human DNA. Unlike in other sci-fi movies, there's no reversal of the transformation, and no happy ending awaiting Seth, which makes the story even more impressive.

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