The Difference Between Science Fiction and Fantasy: What Every Screenwriter Needs to Know

Jeremy Robinson examines the differences between the genres of science fiction and fantasy. Knowing these differences is critical for any screenwriter or author in these genres.
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Jeremy Robinson examines the differences between the genres of science fiction and fantasy. Knowing these differences is critical for any screenwriter or author in these genres.

Jeremy Robinson is the co-author of The Screenplay Workbook, the screenwriter of many science fiction and fantasy scripts (Into The Void, Raising The Past, Missing Time, Believing In Aaron, etc.), and an internationally bestselling genre-spanning author of more than fifty novels and novellas. Twitter: @JRobinsonAuthor

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We all know him: Kal-El, the last son of Krypton. He's faster than a speeding bullet, more powerful than a locomotive and is able to leap tall buildings in a single bound. Known as "the man of steel," Superman emulates truth, justice and the American way. Most of us love, or at least like him. Given the choice of superpowers to pick from, I imagine most of us would choose his. But to the writer, and more specifically, the screenwriter, what is Superman?

Jeremy Robinson examines the differences between the genres of science fiction and fantasy. Knowing these differences is critical for any screenwriter or author in these genres.

Is Superman a product of science fiction? Let's look. He's an alien from the planet Krypton. He flies to Earth in a technologically advanced spacecraft—the same technology that creates his fortress of solitude in the frozen arctic. His arch nemesis, Lex Luthor, is an evil genius who uses advanced technology in never-ending attempts to thwart, kill and otherwise maim Superman. It's settled then; Superman is science fiction.

Or is it? Look closer. He's bulletproof, can fly, is super strong and fast, with X-ray heat vision, freezing breath and super hearing. Superman's powers break every law of physics with no explanation other than the fact that he's an alien. Clearly then, Superman must fall within the mysterious genre of fantasy.

In fact, Superman is both the product of science fiction and fantasy. He is an amalgam of two genres whose elements are polar opposites, yet whose fan bases are identical. That's right; science fiction and fantasy are not the same. Netflix might show them together, but two genres couldn't be more different, and you, as a screenwriter, should know this.

In sci-fi and fantasy screenwriting a thought process exists that is different from any other genre. By the very nature of these genres there is something, as minor as it may be, that seems abnormal to the world we live in. Sometimes the entire universe evolves differently, like in The Lord of the Rings. Other times the world emulates a near-mirror image to our own, such as in Enemy of the State. In either case, story elements propagate, free from the confines of the real world. These elements are schemed and developed in advance for one sole reason: believability.

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It is utterly important that you, as a science-fiction or fantasy screenwriter, know your genre, or no one will believe the world you've created. Watching films, especially sci-fi and fantasy, is an escapist pleasure, heightened by the unreal becoming real. This is why a film like The Matrix became such a massive success. It takes our world and twists it inside out so believably that you're left questioning reality by the end of the movie.

The key to believability in sci-fi and fantasy is to know the rules of your genre and never break them.

What Defines Science Fiction?

You may have difficulty with this question—possibly because you've never really thought about it. Ask yourself this: Is Star Wars science fiction? Of course the answer is yes ... right? There are spaceships, aliens, laser blasters and light sabers. Without a doubt, Star Wars is science fiction. Well, not entirely. So, what makes Star Wars not science fiction?

Science Fiction. Two words. Let's look at them separately. Science is defined in Webster's New World Dictionary as, "systemized knowledge derived from observation, study, etc." This is to say that science knows things are real because they are observable in the real world around us. Not only must they be observable, but repeatable. A fluke or random event isn't considered scientific fact unless it can be repeated, simulated and observed by trained scientists whose scrutinizing gaze can confirm that it does, in fact, exist.

Now let's look at the word fiction in the same dictionary. Fiction is defined as, "any literary work with imaginary characters and events." Certainly, Star Wars fits into this category: it's fictitious. That's an undeniable fact. But science fiction is fiction (imaginary characters and events) bound by the observable and repeatable laws of science. Granted, the laws of science are always expanding and changing, and screenwriters should feel free to develop stories which contain science that does not yet, or may never exist.

Jeremy Robinson examines the differences between the genres of science fiction and fantasy. Knowing these differences is critical for any screenwriter or author in these genres.

Now look at the major theme of the Star Wars universe: The Force. What is it? How does it work? We're told it's in us, all around us; a magical force that enables certain characters, Jedi Knights, to perform such amazing feats as: levitation, telekinesis, mind control and lightning bolts from finger tips—the list goes on and on, with no scientific explanation in sight. The Force alone separates Star Wars from the world of pure science fiction. This doesn't make Star Wars bad science fiction; it simply makes it a mixture of sci-fi and fantasy.

In science fiction, your creations need to make sense within the natural laws of the universe (our universe.) Going back to Superman, how does he fly? Does he have a jet pack? Wings? Does his body fill with helium? No, he simply wills himself to fly, and he does so because Earth's yellow sun gives him super powers (Krypton's sun was red). This is pure fantasy. There is no scientific reason for Superman's powers, thus he'll remain an icon of the fantasy genre.

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How then, can a screenplay with super-powered characters remain science fiction? Simple, create a scientific reason for the powers to exist. Yes, this is possible. Take The Matrix for example. By the film's end, Neo can fly, stop bullets in mid-air and move with superhuman speed. The real question is, how? We learn that Neo's world is a neurally based interactive simulation-basically a virtual reality video game in which the entire population of Earth lives out their lives. As we all know, rules in computer simulations and video games can be broken, allowing characters to fly and have other god-like powers. Science rules the world of The Matrix, a perfect example of superpowers within the realm of pure science fiction.

Basically, if the fantastical elements in your story can't be explained by science, then it's not pure science fiction. And if you're not writing strictly science fiction, then you've got a whole new ballgame called fantasy.

What Defines Fantasy?

Fantasy is anything you create from your imagination that has no scientific reason for existing. In the world of fantasy, things just are. You don't need to explain why one character can fly, while another breathes fire; they're accepted as facts because in the world of fantasy, anything is possible.

As with Superman, most people make the assumption that superheroes are generally science fiction. This is not true. In most superhero comic books, whether they are D.C., Marvel or Image comics, fantasy rules the universe. Let's look at the Justice League by D.C. Comics and separate the characters into sci-fi and fantasy categories. While the Justice League as a whole has not been seen on the silver screen, all have appeared on TV in the 1970's Super Friends series and most recently on the Cartoon Network's Justice League animated series.

• Superman: We already know where he stands, and until someone explains how exactly Kal-El's alien biology allows him to fly, he will remain a figure of fantasy.

• Green Lantern: He wears a powerful ring which allows him to create solid objects and energy beams by simply imagining them. How does the ring know what GL is imagining? How does the ring create solid objects? Science can't explain these things. GL is fantasy.

• Wonder Woman: She's an Amazon princess with super strength, an invisible jet (the old school Wonder Woman anyway), the skill and speed to block bullets with wrist bands, and a magic lasso. Fantasy!

• The Flash: He gained his powers when chemicals spilled on him, speeding up his metabolism and giving him super speed. There is a scientific explanation for how he got his powers but there is no explanation of how they work internally, how his human body withstands the punishment of speed. Flash falls into the fantasy category.

• J'onn J'onzz, the Martian Manhunter: He's an alien. Good science fiction, right? Well, he also has telepathy, can transform into objects and people, is super strong, can phase through solid objects and can fly. Why? Just because he's an alien? That's not a scientific answer. J'onn's fantasy as well.

Jeremy Robinson examines the differences between the genres of science fiction and fantasy. Knowing these differences is critical for any screenwriter or author in these genres.

• Aquaman: He can breathe underwater (without gills) and can communicate mentally with sea creatures. Fantasy.

• Batman: He uses high-tech gadgets, is a master of martial arts as well as a super sleuth using the advanced technology of his own creation. He obeys every natural law of physics (except in Batman IV, ugh). Batman is the only member of the Justice League who is pure science fiction.

There is a fine line between what is science fiction and fantasy, and if you cross it, even just a little, your story becomes fantasy, and the laws of physics and the known world become moot. Let's take a closer look at The Flash. The audience believes that his powers exist, but we accept it only because he is a character of fantasy. If he were bound by the laws of physics he wouldn't be able to do the things he does. Do you know Flash can run at the speed of light? It's true, but scientifically it is impossible. His legs would shatter from the speed and ever-increasing weight as he approached the speed of light. Flash is super fast, but he is not super strong. In every other way, he is a normal human. In a world bound by science, Flash would die from his own speed. But being a character of fantasy, Flash is able to break the laws of physics and do so believably.

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There is another section of the fantasy genre that is often clumped in with the horror genre: the supernatural. Poltergeist, Exorcist, Nightmare on Elm Street, The Sixth Sense and others explore the world of the spiritual and supernatural, but they also break the laws of physics. The powers of ghosts to move objects, to physically manifest themselves, to communicate with the living are lunacy to the science world. Such things have never been proven to be real by science, and unless you can provide a logical scientific explanation for them in your screenplay, they remain figments of the imagination. Not only do the spiritual elements of these stories break the laws of physics, so do the human characters. They communicate with the dead, cast out demons, battle in the dream world and physically travel to the spiritual realm. These stories scream fantasy, but by their screaming are dubbed horror, suspense and supernatural thrillers. However, at their cores, they remain part of the fantasy realm, and it's important to remember this when writing a supernatural story.

The last, and most grand, expression of fantasy writing is pure fantasy, in which science ceases to exist, and the spiritual world is part of the everyday life. Pure fantasy, with its vast worlds of imagination, doesn't need a smidge of science to make it believable or authentic.

Though science never hurts fantasy, because even in purely fantastic worlds, science exists-it's just not a requirement. In fact, science is often replaced by magic. Who are the characters that know and understand the world in fantasy? Magicians, sorceresses, warlocks and wizards are the ones who can understand the way the world works and can manipulate it. They are the equivalent of scientists in the realms of fantasy.

The Lord of the Rings is a perfect example of pure fantasy. No one ever explains how the ring turns people invisible or how Gandalf creates fireballs. And no one wants to know. We have every manner of creature, each with its own powers, each with its own unique laws of physics, and all are completely believable. If you want to create pure fantasy, make sure not to include modern science; there's no need for it. Do, however, feel free to include science explained through the mechanism of magic.

But can fantasy be unbelievable? Yes, it can. When you create your world of fantasy, you intrinsically create natural laws. If gravity exists in your fantasy story, don't have a character suddenly start flying without cause. Sprouting wings or eating a magical acorn will do just fine, but be careful not to break your own rules. It will show.

In general, writing fantasy is extremely rewarding and gives your imagination permission to explore every nook and cranny of possibility. If done right, it has the potential to create new worlds never seen before ... and rake in big bucks, too.

Combining Genres:

Now that we know what separates science fiction and fantasy, how do we go about combining them? Here's a simple rule. Never add fantasy elements to a science fiction story. Always start in the fantasy world and add science fiction. Superman is mostly fantasy, with elements of science fiction added into the story. The Star Wars saga is dependent on elements of fantasy—the science fiction simply backs it up. Adding fantasy to science fiction is a no-no and should be avoided at all costs, or you risk alienating your audience and the reader of your script.

Imagine that you're watching a movie about a mission to Mars. The characters use a spaceship to get to the red planet. Good. They use spacesuits to walk around on the surface. Still good. Then one of the characters, Bob, a normal human in a real world scenario, jumps a 50-foot ravine, Matrix style. Most likely you'll laugh out loud and write off the rest of the movie. Don't write scenes like this in your science fiction screenplay. If you're not sure whether something you've written breaks the laws of science or not, take it out or ask a scientist or science teacher.

The Fifth Element. In every scene we see and hear things like: flying cars, phonic detectors, cells bombarded with slightly greasy solar atoms, cellular hygiene detectors. Sounds like science fiction, doesn't it? But look at the character of Leeloo. She is super strong, impervious to harm, has limitless knowledge, is immortal and is the "fifth element" known as the Supreme Being, whose sole reason for existing is defeating an evil planet by powering a super weapon with her body. Remove Leeloo from the story and you lose the entire story. The science fiction in The Fifth Element backs up the fantasy, and it comes off perfectly. This is the best way to combine sci-fi and fantasy.

In Closing:

Did you know that eight out of the top 10 grossing films of all time are science fiction and fantasy? It's true. But by breaking the rules of science fiction and fantasy, you're guaranteeing that your film will never be added to the list. You're also guaranteeing that when your $100 million movie bombs at the box office because you broke the rules, destroying the audiences' suspension of disbelief, all fingers will be pointed at you.

Need help crafting your sci-fi script? Take our online course,
Writing the Sci-Fi/Fantasy Screenplay


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