Vampire rules are house rules, and every card table plays poker a little differently, and nobody minds, as long as the dealer announces the rules before the first hand and doesn’t change them when he’s losing. Readers are the same. Tell them how your vampires work, then keep your word.
A writer in a big fiction group asked a question I hadn’t thought about. Do vampires in your lore show up on infrared or thermal imaging?
He kept going. If a vampire has no reflection in a mirror, would it show up on film? Does a camera count, or only one that uses a reflected or refracted image? Are vampires invisible to digital imaging? Could they even use a smartphone, when the phone insists on fingerprint or facial recognition? Would the screen recognize their touch?
Then he came up with the best image in the thread. A poor vampire standing at a modern public sink, flapping their hands under the faucet, unable to make the thing turn on.
He answered his own question by the end. If it’s your vampire lore, you can use or ignore any of the tropes that have piled up over the decades, or mix and match them. This kind of vampire can do this, while that kind can’t. He’s right about that.
Where do vampire rules come from?
Most of them come from the last 130 years, and many of them come from movies.
The vampires of older Eastern European folklore were bloated, ruddy corpses that climbed out of their graves to bother the neighbors. Bram Stoker’s Dracula in 1897 gave us the aristocrat. Stoker’s Count casts no reflection. That gave us the famous shaving scene, where Jonathan Harker notices the Count is behind him and the mirror is empty. But Stoker’s Dracula walks around in daylight. He’s weaker during the day.
Daylight doesn’t kill him.
Sunlight as a death sentence came from F. W. Murnau’s Nosferatu in 1922, where the first light of morning destroys Count Orlok. Filmmakers liked it so much that it became the rule. (See also Twilight, where sunlight makes vampires sparkle) Fangs, capes, turning into bats and the need to be invited in each came from a different source, and each writer since has picked from the pile.
So when someone tells you a vampire “can’t” do something, the right answer is “whose vampire?” I covered how the films built the creature over a century in Blood, Myth, and the Undying Dark.
Watch: How to Write Vampires | Writing 101, Morgan M. Steele
Why does Dracula 2000 work so well as vampire lore?
I love vampire movies, and Dracula 2000 is one of my favorites for one reason. It explains the restrictions.
The film’s twist is that Dracula is Judas Iscariot. He betrayed Christ for thirty pieces of silver, tried to hang himself, and was cursed to live on. Suddenly the old weaknesses aren’t random. Silver burns him because silver was the price of the betrayal. Crosses and holy things repel him because of the one he betrayed. The film ends with him hanging again, the way Judas died, as the sun comes up.
Every rule points back to one origin.
I thought that worked very well. A reader who learns the origin can predict the weaknesses, and a reader who can predict them feels clever. That feeling is what keeps them reading. It isn’t a great film by most accounts. Its scores are low, and I covered it alongside three other screen Draculas in the Dracula contrast review. But as a lesson in building vampire rules, it ranks near the top of the list.
What makes the vampire rules in Blade so good?
I also like the rules in Blade, and they work for a completely different reason. Blade treats vampirism as biology.
The vampires in those films are infected. It’s a disease of the blood, and the story treats it like one. There’s a serum that holds back Blade’s thirst, a doctor working on a cure, and an anticoagulant that makes vampires blow apart. Silver, garlic and ultraviolet light are weapons because the vampires’ bodies react to them. Blade is half vampire, a Daywalker, with all of their strengths and none of their weakness to sunlight. Purebloods born as vampires look down on the ones who were turned.
The second film pushes the biology further with the Reapers, a mutation that preys on the vampires themselves. Treat a monster as a disease and it can mutate like one.
The first film also never stops to lecture. You learn the rules by watching them in use, starting with the blood rave in the opening scene. I wrote about that in my Blade trilogy review.
Vampire rules are house rules. Readers will accept almost anything, as long as you announce the rules before the first hand and don’t change them when you’re losing. – Richard LoweShare on X
Would a vampire show up on thermal imaging?
That depends on what your vampire is.
One commenter said no, because vampires are reanimated corpses. A corpse cools to the temperature of the room around it. If your vampire is dead tissue moving by magic, a thermal camera should show a person-shaped cold spot, darker than the wall behind it.
But that opens more questions, and readers will ask them. Does the vampire warm up after feeding, and for how long? Is a freshly fed vampire visible to thermal imaging and a starving one not?
That could be a plot point. A Blade-style vampire with a living, infected body would run warm like anyone else.
Motion-sensor lights add a nice wrinkle. Many of them detect the body heat of a person moving past. A cold vampire could cross a parking lot in the dark without the lights ever coming on.
Can a vampire with no reflection be photographed?
Another commenter offered a popular explanation. Mirrors used to be backed with silver, and silver is the problem. Modern mirrors mostly use aluminum, so some recent stories let vampires appear in a new mirror but not an antique one.
That’s a good example of a rule with a reason. It answers the camera question too. A camera has no silver backing, so under that rule the vampire shows up. Old film photography used silver salts. Your vampire could vanish from a 1950s snapshot and show up fine on a phone.
If your rule is that a vampire has no soul and a mirror shows the soul, then you have to decide whether a camera shows the soul too. Some writers say yes and some say no. The vampires in What We Do in the Shadows can’t see themselves in a mirror, so they draw each other to know how their outfits look.
The joke works because it takes the rule seriously.
Could a vampire use a smartphone?
The old rules run straight into modern life. That collision is a great source of story.
Most touchscreens sense the electrical charge of a finger. Living skin conducts electricity. Most gloves don’t, so the screen ignores a gloved hand. Would a cold, dry corpse finger register? You could say no and give your vampire a stylus and a lot of frustration. Facial recognition on many phones projects infrared light onto your face and reads the pattern with a camera. If your vampire can’t be captured by a camera, the phone won’t unlock. If the rule is about silver, it unlocks fine.
And that public sink? Most automatic faucets bounce infrared light off your hands and wait for it to come back. A vampire with no reflection would stand there forever. A vampire who just doesn’t show up in silver mirrors would wash up like anyone else.
None of these answers is right or wrong.
They’re decisions, and each one changes what your vampire can do in a modern city. A vampire who can’t use a phone, can’t open an automatic door and can’t be seen by a doorbell camera is living a very different life from one who can.
| Technology | How it works | What your rule decides |
|---|---|---|
| Thermal camera | Reads body heat | A room-temperature corpse shows as a cold spot; a living, infected body runs warm |
| Motion-sensor lights | Many detect the heat of a moving body | A cold vampire could cross a dark parking lot without triggering them |
| Mirror | Old mirrors were silver-backed; modern ones mostly aluminum | Under a silver rule, the vampire appears in a new mirror, not an antique one |
| Camera | No silver backing; old film used silver salts | Silver rule: missing from a 1950s snapshot, fine on a phone |
| Touchscreen | Senses the electrical charge of living skin | A cold, dry corpse finger might not register |
| Face unlock | Projects infrared light and reads it with a camera | No camera image means no unlock; a silver rule unlocks fine |
| Automatic faucet | Bounces infrared light off your hands | No reflection means standing there forever |
How do you build your own vampire rules?
Start with the origin. Is your vampire cursed, infected, a different species, a demon wearing a body? Dracula 2000 picked a curse with a story behind it. Blade picked a disease. Everything else follows from that choice. Then decide each weakness and give it a reason that comes from the origin. Sunlight, silver, running water, invitations, mirrors. Keep the ones that fit and drop the ones that don’t. You don’t need all of them.
A vampire with a few well-explained weaknesses is more frightening than one a bulb of garlic can stop. Every weakness is a door the hero can use, and every door you add makes the monster easier to beat. Give him three and make each one cost something to exploit. Silver is expensive. Sunlight only comes at dawn. An invitation has to be tricked out of someone.
Then follow every rule into the modern world. Thermal cameras, phones, doorbell cameras, automatic sinks, blood banks, hospitals. Daybreakers took one rule to its end point, a world where vampires are the majority and the blood is running out.
Finally, write the rules down for yourself and keep them consistent. If your vampire can’t cross running water in chapter three, he can’t wade across a creek in chapter twenty because the plot needs him to. Readers forgive strange rules. They don’t forgive broken ones. The same principle runs through my articles on fantasy world building and horror writing.
Pick the origin first, and let every weakness and modern consequence follow from it.
Should you explain your vampire rules to the reader?
Show them in use first. Blade shows the rules through action. Dracula 2000 saves the big explanation for a reveal. Both work. What doesn’t work is a chapter where a character sits down and reads the rulebook aloud. Let the reader see the vampire flinch from silver. Let them watch it fail to unlock a phone. Then, when the explanation comes, it pays off something they already noticed.
My take
Pick the origin first, and every other rule follows from it. Dracula 2000 and Blade work because their weaknesses mean something. Give your vampire three weaknesses and make each one expensive to exploit. Then drag him through the modern world, phones, thermal cameras and doorbell cameras included, because your readers will. Write the rules down and never break them for the plot’s convenience. Readers forgive strange rules, but they won’t forgive you for breaking one.
My own vampire stories
Not a novel yet. I plan to. My fiction section has two vampire stories, Crimson Hunger, about the hunger itself, and The Crimson Cleanse, about a three-hundred-year-old vampire with a portion-control problem who ends up in a support group. I want to write more flash and short stories with vampires in them.
If you love vampire movies too, the greatest vampire films list is a good place to study how other storytellers built their rules. The writing hub has more on world building and genre fiction, and if you’d like help working out the rules for your own monsters, my book coaching covers that. Announce your house rules before the first hand. Then play by them, even when the sun’s coming up.
