In most cases, there are fantasy monsters like faeries and sci-fi monsters like aliens, but at least one horror icon seems to comfortably occupy both. What is it about vampires that make them so easily integrated into the past, the future, the domestic world, and the depths of space?

Most horror fans know the origin of vampires. 18th-century superstition mixed with the semi-true stories of Elizabeth Bathory and Vlad III gave way to groundbreaking fiction. Sheridan Le Fanu's Carmilla is popularly considered the first recorded piece, but Bram Stoker's Dracula is the one that defined the genre. From those humble beginnings, the concept has grown to unimaginable variety.

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Those early examples of vampire fiction are strictly fantastical. There's little to no science to speak of. Dracula is magical in nature, his powers and weaknesses hand-crafted by the Christian god as a form of punishment. Over the years, however, vampires have shifted from horror monsters to one of the countless fantasy races. There's seemingly no fictional world in which vampires can't pop up. The rules are loose, most fictional vampires pick and choose from the list of hallmarks established in the early works. It's fair to say that vampire fiction is its own genre, unbound by any need for consistent appearance in a specific type of story. With that in mind, there are a few interesting themes that emerge when vampires cross over into the world of science fiction.

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It didn't take too long for the vampire to make its way into outer space. The popular suggestion of real-life vampires came in the early 1700s and the early tales of vampires in space came in the early 1900s. Perhaps the seminal stories about space-bound vampires came in 1908 when Gustave Le Rouge's Vampires of Mars was released. That strange tale followed classic sci-fi tropes, mixing planetary romance with cosmic horror as a team of swashbuckling space heroes met with a planet of vampires. This novel's creatures are the native inhabitants of Mars, humanoid monsters with huge bat wings and deadly fangs. This concept of alien species that happen to closely match human descriptions of vampires is common in sci-fi stories.

Most space-hopping fiction has at least one or two planets that are inhabited by an alien creature that shares some or all traits with vampires. Doctor Who, for example, has tangled with a few versions of vampires. Within that long-running series' lore, vampires are a sort-of parasite that is descendant from a more powerful species, and every sapient species deals with a vampire phase. The great horror director Tobe Hooper's 1985 film Lifeforce featured the invasion of a group of deadly space vampires who threatened to consume the Earth's living souls. Mario Bava's thrilling Giallo film Planet of the Vampires sees a crew of space explorers crash-land on a hostile planet, whereupon their dead rise and attack. Aliens as vampires is a fairly common concept in sci-fi, largely serving as an excuse to get the creatures into a sci-fi narrative.

Many, though probably not most, vampire stories are inherently antagonistic. They depict the conflict between mankind and the creatures of the night. The trouble is, in a fair fight, no human being can reliably defeat a vampire. One common way of solving this issue and allowing the conflict to grow in scale is arming mankind with futuristic or specialized weaponry. This is the ethos of works like Blade, Ultraviolet, and Underworld. These works tie in with another trend of sci-fi vampires, scientific explanations for their unique condition. Sometimes it's the result of unorthodox experimentation, other times it's a rare blood condition, and other works describe it as a plague. These are examples of reaching a familiar conclusion through a new route. Telling the classic tale of humans slaying monsters, now with the benefit of scientific enlightenment.

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Science fiction and vampires mix well, easily transitioning the tropes of the genre to the classic sci-fi settings. This concept works for several reasons. The concept of something that looks just like a normal human, but behaves as an unrepentant monster is common and relatable fictional fodder. Vampires specifically represent themes of sexuality, class warfare, and the abuse and commodification of the poor by the rich. These themes are no less relevant to the modern day than they were when they emerged, and most sci-fi authors see them as relevant to the future. Cyberpunk dystopia, nightmarish outcomes of the future, and the ongoing cyclical nature of progress and regression are all just as common to sci-fi as they are to everyday life. With all of that in mind, vampires work as thoughtless monsters of the week and as entries in the ongoing mythos that was defined hundreds of years ago.

The truth about vampires in fiction is that they work wherever they need to. Vampires may as well be a genre of fiction on their own, but that genre's crossover with science fiction is among the most interesting in the medium.

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