Standing in the dark staring into a mirror summoning Bloody Mary by chanting her name is a terrifying classic sleepover ritual.

Here's the basic premise.

If you chant "Bloody Mary" while looking in a mirror in a dark room, preferably a bathroom, the face of this spectral woman will appear alongside you.

The mirror is a symbol of revelation and self-reflection.

It forces us to see what others see.

In fiction, mirrors and reflections often serve as tools for confrontation like in "Harry Potter" or "Snow White."

Even when serving as portals or windows to alternative worlds, like an "Alice Through the Looking Glass" or "Oculus," the journey of self-discovery or revelation is paramount.

[dramatic music] With Bloody Mary, that truth might just be a good fright, or her appearance might tell your future, grant you a wish, or perhaps even kill you.

I'm Dr. Emily Zarka and this is "Monstrum."

If you were unlucky enough to summon Bloody Mary, there's no real standard of what you'll see.

By some accounts, she's hideously mutilated, but in others, she is beautiful but bloody.

More commonly though, every aspect of her appearance is vague.

Her spectral origin story is all over the place too.

She's tragically disfigured and out for revenge or she's been killed by a jealous lover.

There's even versions where she was a witch burned at the stake in Salem.

In some legends, she's connected to a cult.

Where she comes from and what she looks like is less important than the ritual that summons her.

Three things are almost always required, a dark room, a mirror, and a chant.

You have to say her name anywhere from three to 100 times, and in some accounts, you must have a single candle burning.

In others, the summoning must occur in a bathroom.

A few tales even specify you have to run water, flush the toilet, or spin around three times.

Still others note that you must run out of the room when you see her or she can cause you harm.

And in some versions of the legend, you even have to offer your own blood.

What happens from there?

She might reveal your future, but in most stories she's threatening.

She will frighten you out of the room or even attack you in the real world.

In one particularly gruesome variation, if you touch the mirror, she'll be able to drag you into her realm and kill you.

Sound ambiguous?

Yeah, that's kind of the point, at least in my mind.

Not knowing exactly what is going to happen or who is going to appear in the mirror is part of the attraction of this legend, and a reason to try it yourself.

There are three common elements to the legend.

Let's break it down.

First, the dark room.

Fact, it's scary to be in the dark, especially if you're asking for something supernatural to happen.

Our eyes tend to play tricks on us in the dark.

Seeing a distorted reflection in the mirror is possible when darkness and flickering light are in play.

In the case of Bloody Mary, overall spookiness and fear are common culprits too.

Second, the mirror.

Mirrors serve as symbolic boundaries, spaces where the real is confronted while offering the possibility of alternative ways of seeing or being.

After all, there is the idea of the mirror realm.

The basic concept of the mirror realm is that there is an opposite, usually darker world that exists alongside our own.

And mirrors serve as the portals between the two.

Even before bloody Mary entered into the picture, the idea existed that with some kind of ritual, otherworldly figures could appear inside of mirrors.

In some lore, a malicious magic practitioner could even bind a spirit or the devil to a mirror.

As a threat of real persecution for witchcraft declined, the idea of a cult play or lighthearted dabbling in a cult and magical practices rose in popularity.

Young adults, particularly women, turned to the mirror for divination rituals, often with the intention of identifying their future spouse.

Knowledge of these playful rituals was popular enough that in the early 20th century, as the postcard industry boomed, cards depicting women engaging in divination rituals were popular during the fall season, often corresponding to Halloween.

In one example, a girl stands in front of mirrors holding a candle while the nebulous face of a handsome male figure appears over her shoulder.

But not all cards show such appealing prospects.

Other versions show a stereotypical witch or the frightening ghost of a man.

Connecting the mirror ritual back to its more nefarious associations.

It's hard to guess how seriously rituals like these were taken.

Although the playful commodification of the events suggests at least some level of carefree participation.

The mirror ritual offers a form of boundary rebellion with little risk of true danger, an appealing prospect for teenagers.

And finally, the chant, or what puts the Mary in Bloody Mary.

The repeated name is always a female one, Bloody Mary of course, but also Mary Worth, Mary Ruth, Black Madame, Mary Lou, Mary Johnson, Mary Weather, and Mary Whales, for example.

Mary is a common name, but some of these women stand out more than others in folklore.

Take Mary Worth, for example, said to have a disfigured face either from genetics or a bad accident, she resented her looks.

So much so that she put a curse upon the mirror she gazed into one day, and it shattered, killing her.

If you stare into a mirror and summon Mary Worth, she will appear at a distance in the reflection moving closer and closer until she shatters the mirror.

And if this happens, you'll never again be able to look into a mirror without seeing her reflection.

Or there's Mary Whales.

This Mary was a young woman who was killed when she was run over by a truck.

Six years after she died, a couple saw her trying to hitchhike.

Bleeding and wet, she had scratches on her face.

You can look in a mirror and summon her ghost by saying "I do believe in Mary Whales" somewhere between 10 or 100 times.

Given the hitchhiking ghost element, this urban legend might be a regional variant combining elements of other legends and monsters, like the vanishing hitchhiker, La Llorona, or Mary Worth.

And let's address the royal elephant in the room.

Only one other female figure in history has been called Bloody Mary, Mary Tudor or Queen Mary I.

Born to Katherine of Aragon and King Henry VIII in 1516, princess Mary was named after her beautiful aunt, an attribute she came to embody.

Scorned by her father upon his second marriage, she would eventually be declared his rightful heir in his will and took the throne in 1553.

Her reign was fraught with tension.

At Mary's command, hundreds of Protestants were burned at the stake as heretics.

Despite this violence, it wasn't until her half Sister Queen Elizabeth's rule that she would become known as Bloody Mary, likely as an attempt to diminish or at least tarnish her historical significance.

The catchy name gained popularity as the 17th century wore on.

So by the time the infamous mirror summoning postcards popped up in the 20th century, the nickname had been around for hundreds of years.

To me, there seems to be an easy connection between the royal and real Bloody Mary and the folkloric monster.

Both of their stories deal with the cultural perception of beauty and of stories being rewritten by whomever is telling them, casting the Marys as both victims and villains.

When we consider where the summoning of Bloody Mary often occurs, in bathrooms, and by whom, young women, another interpretation becomes apparent.

Bathrooms are uniquely liminal places.

Whether private or public, they are rooms within larger spaces where private acts occur-- bodily functions often seen as gross or taboo.

Folklorist Alan Dundes' freudian reading of Bloody Mary proposes a metaphorical representation to the onset of menstruation.

He argues that the mirror summoning ritual serves as a right of passage into puberty, a journey that is both feared and celebrated.

If we accept this reading of the legend, then bloody Mary is a warning, not only about the inevitability of the sudden bleeding women will likely deal with in the bathroom, but of puberty in general.

An adolescent girl gazing in the mirror may be met with both trepidation and wonder at her own changing appearance.

And that's before you factor in the pressures of an entire beauty industry dedicated to making her want to alter the reflection staring back at her.

Not to mention the expectations of whatever standard of attractiveness is being promoted in culture at the time.

Perhaps then, it is unsurprising that the Mary in the mirror is always frightening when summoned.

It also helps explain why Bloody Mary is a common figure at sleepovers, which often occur during puberty and into the teen years.

Telling scary stories, playing games, and pulling pranks are all common at sleepovers, at least the ones I went to.

And Bloody Mary is an option that can fit into all three categories for just the right age group.

It's worth noting that the participant in the Bloody Mary ritual is always in control, or appears to be.

They're the one who says the name, but they can also turn on the lights or run away.

The ghost is summoned.

It does not simply appear.

Unlike other monstrous spectral encounters or ghostly women like the Banshee or La Llorona, this notorious female specter must be invited in, which partially diminishes her power, or at least her reach, and removes some of Bloody Mary's potential to cause terror.

So our ability to control the appearance of Bloody Mary takes a little bit of the danger out of it.

Fear becomes fun.

The idea existed that with some kind of ritual...

Some kind of ritual, pause.

(crew) Rolling by the way, but... Ooh, cut that.