Welcome on this Weird Wednesday! We’re about to go for a nighttime stroll through a marsh, and it looks like our friend Will’s brought a flashlight.

A will-o’-the-wisp is a type of ghost light, which is a flickering or moving light visible in the wilderness on dark nights, without any obvious source. Will-o’-the-wisps specifically refer to lights glowing over marshes or bogs. Sometimes people get the urge to chase after these lights—possibly to an unexpected death by drowning. 

But guess what—unlike some of the other paranormal topics discussed on this blog, ghost lights are actually real. So what the heck are they? Let’s look at some theories:

Sometimes the Earth just makes lights

Let’s get reality out of the way first. There are different explanations for ghost lights, depending on where they are, including bioluminescence (living things glow), chemiluminescence (chemicals glow), piezoelectricity (earthquakes glow), and reflections of human-made lights. (Some people add ball lightning, but that’s a weird topic all by itself.) A will-o’-the-wisp, which glows over marshes or bogs, is probably common gasses which ignite easily from natural causes and can move with the wind. So that’s very cool! But folklore’s got some fun stuff to say too:

Putting the “ghost” in ghost light

In some traditions, ghost lights are death omens: if a light is seen, someone is going to die. Multiple lights? Prepare for a mass funeral. Sometimes the person who sees the light is doomed, and sometimes it could be anyone who will be in the area in the near future. Closely related and somehow even more creepy are you’re-going-to-find-a-dead-body omens: for example, a ghost light might mark a hidden burial, or appear on a beach right before a drowned sailor washes up there.

Ghost lights can also be associated with, well, ghosts. A light might mark an undiscovered murder scene, or even be carried by a ghost, who’s wandering around with a lantern for various creepy reasons. Which has a lot in common with another common explanation:

Will-o’-the-Wisp by Arnold Bocklin, 1862

Some jerk with a light

The story goes like this: a man named Will commits many naughty deeds. Upon his death, the devil comes to collect his soul, but Will tricks Old Nick into a trap and asks for forgiveness as payment for setting him free. The devil grants this request—Mr. Naughty is saved from hell! But unsurprisingly, heaven doesn’t want him either. So Will is doomed to wander Earth forever, with just a coal from hell for a light. And of course, he continues his naughty deeds, using his light to lead travelers into a dangerous marsh, a confusing forest, or to the edge of a cliff. (If you think this sounds like the legend behind the jack-o’-lantern, you would be right. Will-o’-the-wisp and Jack-o’-lantern are sometimes versions of the same story.)

But there are other naughty characters out there who would love to lead a traveler astray: the fae, for example, or Puck; in modern times, aliens. These trickster lights are known as ignis fatuus, or “foolish fire.” But it begs the question: why would somebody follow a random light off the road and into a swamp? Well, perhaps they’re looking for:


In the novel Dracula, poor Jonathan Harker endures a perilous nighttime carriage ride, during which the creepy coachman repeatedly stops to make piles of stones in places where blue flames are blazing. Apparently, Jonathan has managed to arrive in the area on the eve of St. George’s Day, a night when evil freely walks the land. It’s also the one night a year when buried treasure can be located by blue flames. Anyone brave enough to go out on that night can mark the treasures’ locations and dig them up later, which probably explains why Dracula’s got piles of gold coins lying around his castle.

In other tales, it’s said these treasure-lights are actually lanterns held by kindly-but-still-sort-of-mischievous beings who will gladly lead a traveler to buried wealth. Or maybe to the edge of a cliff instead. I’m not sure I would take the chance, personally.

And now for some wispy writing prompts!

  • Bring out your dead. Death omens are common in folklore, as are supernatural signs that point to the undiscovered body of a murder victim. But a flame marking a place where a dead body will arrive in the near future is super creepy. What on earth would someone do with that information? Call the coroner to be on standby? Tell the police to stake out the place in case a murderer shows up with a corpse? Have paramedics hang out in case some random guy has a heart attack? The question is the same as always when dealing with death omens: can the future be changed? Is the purpose of the omen to give some supernatural forewarning that only serves to panic people who can’t do anything about it, or is it meant to be a last-ditch effort to save someone’s life? Sounds like a horror story in the making.

  • Just a little filthy lucre buys a lot of things. So Dracula probably didn’t give a flying mirror (haha) about the supernatural provenance of the gold he dug up, but the rest of us might want to take more care. Because what are the odds that treasure marked by blue flame on the most evil night of the year is not cursed? A story could get into different aspects of this idea: where does the gold come from, anyway? (In Dracula, it’s wealth hidden during times of war.) Who buried it? Are they planning to come back and get it? Why would a treasure cause a blue flame once a year? And if you did manage to get your hands on the treasure, is there a way to un-curse it? Perhaps if you give most of it to good causes, or have it blessed by a priest—unless of course it’s so unalterably cursed that the priest dies and the good causes have a horrible spell of bad luck…

  • Some kindly person with a light. There are most definitely jerks wandering this earth, but there are also plenty of nice people. So why not have a helpful character who roams around with a lantern, trying to save people who get lost in a marsh in the dark of night? It could be the ghost of someone who drowned in the bog, a fairy fond of humans, a benevolent alien, or an angel. It could also be a former jerk who is serving a punishment for leading people astray, required to save one person for each one he doomed. Or it could even be a living person who knows the marsh well and keeps watch for errant treasure-hunters getting themselves in trouble. Might there be a supernatural reward for such a sweet soul?

  • Mad science. Naturally, real scientists have tried recreating ghost lights, as a means to identify and understand them. You could take this into the realm of fiction by having a scientist discover that will-o’-the-wisps are not natural phenomena, but in fact really are some undead dude named Will who wants to laugh at you when your shoes get stuck in the mud. Maybe Dr. Science and Will become friends. (Maybe they become more than friends.) Or maybe they’re sworn enemies, but Dr. Science wants Will to find peace so he’ll quit being a nuisance. And all the while Dr. Science is fuming because nobody is going to believe him about those lights being a sketchy (and inconveniently attractive) ghost with a lantern.

  • Fire alarm. What if the fire was not just a little wisp but like, a fire? What if Will could set a building or farm ablaze with his bit of coal, by accident or otherwise? The fae might want to burn down a home built on a fairy fort, or a ghost the house where they were murdered. A reckless trickster could start a forest fire while trying to get a traveler lost. Or you could have an undead firebug who tricked the devil into giving him that ever-burning coal and now lays waste to the countryside. How could someone defeat such a character? Is it even possible to put out a supernatural fire?

Thanks for spending your Wednesday here! Maybe next time we should bring our own flashlights, though.

Want to chat about the blog? Did you use one of the prompts? Hit me up on social media.

If you like unsettling legends, you can check out my story Branwen and the Three Ravens in the anthology Clamour and Mischief from Clan Destine Press. The creepy adventures of a woman trying to free her brothers from a curse.

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Sources & further reading:

Clark, Jerome. “Ghost Lights.” Unexplained! Visible Ink Press, 1999. On Goodreads

Guiley, Rosemary Ellen. “Ghost Lights.” Atlas of the Mysterious in North America. Facts on File, 1995. On Goodreads

Guiley, Rosemary Ellen. “Ghost Lights” and “Ignis Fatuus.” The Encyclopedia of Ghosts and Spirits. Facts on File, 1992. On Goodreads 

Will-o’-the-wisp: Wikipedia

Atmospheric Ghost Lights: Wikipedia

Read Dracula by Bram Stoker online (Novel is in the public domain)