← Back to Podcast/Unsolved: The Ciphers of California's Zodiac
Episode Transcript

Unsolved: The Ciphers of California's Zodiac

Unsolved: The Ciphers of California's Zodiac

Become a supporter of this podcast: https://www.spreaker.com/podcast/missing-persons-mysteries--5624803/support.

Speaker 1: Okay, friend, go ahead and throw that last log on

the fire, and let's watch the embers glow as red

as a harvest moon. Now, we've been on quite a

journey tonight, haven't we? We've chased ghosts out across the

freezing ocean, waded through the choking mud of the Louisiana Bayou,

and dug deep into the ancient dirt to find the

nightmares of old. We've talked about curses and treasures, and

the things the earth swallowed whole. But, as the night

gets long and the shadows crawl all the way up

to the ceiling, I want to bring you back home.

I want to bring you to a place of paved roads, streetlights,

and police sirens. Because the most terrifying monster of all

is the cursed temple or scaly beast in the swamp.

Oh no. The most terrifying monster is the one who

does away with people for the sheer bloody thrill of it.

And then writes you a letter to brag about the

fun he had. So let's take a walk through the

creeping heavy fog of San Francisco in the late 1960s.

Let's talk about a phantom in a hood. Let's talk

about the unbreakable ciphers of the Zodiac Killer. Now, back

in the late 1960s, the San Francisco Bay Area was

supposed to be the capital of peace and love. Young

folks were putting flowers in their hair, strumming guitars, and

dreaming of a brighter tomorrow. But the universe demands a balance, friends.

Wherever there's a blinding light, an impossibly dark shadow is

bound to fall. Now, that shadow... started creeping along the

lonely country roads and secluded lover's lanes of Vallejo and Benicia, California.

It was a predator who hunted in the dark, targeting

young couples sitting in parked cars. He didn't rob them.

He didn't want their cars or their wallets. He just

walked up to the windows with a flashlight in one

hand and a weapon in the other, and he shattered

the quiet night. Sometimes he struck in the dead of winter.

Sometimes he struck on the 4th of July. Out at

Lake Berryessa, He even attacked a couple in the broad daylight,

wearing a terrifying hand-sewn black executioner's hood with a bizarre

symbol stitched onto the chest, a circle with a cross

running right through it, like the crosshairs of a rifle scope.

He left bodies in the gravel, and he left the

whole state of California trembling in absolute cold sweat terror. But,

if you can believe it, all that wasn't the worst part, friends.

Oh no. The worst part was that he wanted to

talk about it. Now, in the summer of 1969, the

editors at three major Bay Area newspapers opened their morning

mail and found letters written in blue felt-tip pen. The

handwriting was frantic, slanted, and strange. The sender claimed responsibility

for the murders. To prove it, he included details that

only the cops and the killer could possibly know. How

many shots were fired, the brand of ammunition, the exact

position of those left behind. Now, he didn't just confess.

He demanded the spotlight. He demanded that the newspapers print

his letters on the front page, or else he would

go on another weekend rampage. And then, he introduced himself.

This is the Zodiac speaking. But he didn't just send angry,

boastful letters. Oh no. The Zodiac wanted to play a game.

Along with his letters, he sent cryptograms. Blocks of baffling,

chaotic symbols. He used a mix of Greek letters, weather symbols,

Morse code, and strange geometric shapes he seemed to have

made up right out of his own twisted head. He

claimed that if the police could crack the codes, they

would find his true identity. He was dangling the keys

to the cell right in front of their faces, daring

them to reach out and grab them. Now, the first

cipher he sent was broken into three parts, totaling 408 symbols.

The FBI, the CIA, and Naval Intelligence all took a

crack at it. Their massive mainframe computers hummed and whirred,

spitting out reams of useless data, the government was stumped.

But down in Salinas, a high school history teacher named

Don Hardin and his wife, Betty, sat at their kitchen

table with a pencil and a piece of scratch paper.

They figured somebody like the Zodiac had an ego the

size of a mountain. They guessed the message probably started

with the word I and probably included the word kill somewhere. So,

working late into the night, just two ordinary folks drinking

coffee in their kitchen They peeled back the Zodiac's first

layer of armor. They cracked the 408 cipher. But when

the translation came out, there was no name. There was

no address. There was just the chilling, dead-eyed philosophy of

a monster. The Zodiac wasn't hiding a confession. He was

hiding a nightmare. He claimed he was collecting souls to

serve as his slaves in the afterlife. Now furious that

two amateurs had bested his puzzle, the Zodiac doubled down.

He sent a new cipher, this one containing 340 characters.

And this time, he didn't make any mistakes. The 340

cipher became a legend of cryptography. For over 50 years,

it defied every supercomputer, every algorithm, and every brilliant mind

that tried to pry it open. Until a team of

international codebreakers finally cracked it in the winter of 2020.

But once again, there was no name. Just more rambling,

mocking taunts from a ghost. But here is where the

story turns truly cold, friend. Here is the mystery that

still keeps the FBI agents up at night, staring at

the ceiling and grinding their teeth. You see, in April

of 1970, the Zodiac sent a letter to the San

Francisco Chronicle. It started with his usual boastful greeting. This

is the Zodiac speaking. Then he wrote a single line

of plain English that made the blood run cold in

the veins of every detective in California. Quoting here, By

the way, have you cracked the last cipher I sent you?

My name is... End quote. And right below those words,

he didn't write a name. He wrote a brand new cipher.

It was tiny. Just 13 symbols. A mix of circle dates,

alphabetical letters and crosses. They called it the Z13. 13

little marks of ink on a piece of yellow paper.

It's the holy grail of modern true crime. The Zodiac

looked the entire world dead in the eye and said,

Here I am. Here's my true name. Come and get me. But,

you see, the terrible truth of cryptography is that a

code that short is mathematically impossible to break with absolute certainty.

There simply aren't enough repeating characters to find a pattern.

You could literally plug a thousand different names into those

13 symbols and they would all technically fit. But it's

like trying to pick a lock with a piece of

wet string. He didn't just create a puzzle. He created

a trap. He built a labyrinth with no exits. knowing

full well that the police would exhaust themselves trying to

find the center. Later that year, he sent one more puzzle,

the Z-32. 32 symbols containing the location of a bomb

he claimed he'd buried under a school bus route. Thankfully,

the bomb never went off, or perhaps it never existed

at all. But, just like his name, those 32 symbols

have stubbornly, absolutely resisted every attempt to crack them. So,

the Zodiac Killer continued to send letters for a few

more years, complaining about bad newspaper coverage, taking credit for

demises he likely didn't commit, and demanding the people of

San Francisco wear buttons with his crosshair symbol on them.

And then, one day, he just stopped. The letters ceased.

The crimes faded away. The thick, rolling fog of the

Bay Area simply swallowed him whole. The police investigated thousands

of suspects. They looked at a disgraced schoolteacher who liked

to watch people. They looked at a creepy newspaper man.

They looked at a heavyset fellow who had the same

boot size as the footprints left at Lake Berryessa. But

the DNA didn't match. The handwriting was always just a

little bit off. They could never put handcuffs on any

of them. The Zodiac slipped through their fingers like water, friends. Now,

I want you to think about that, friends, as the

fire dies down to ash. Think about the man who

wore the executioner's hood. If he was in his 20s

or 30s back in 1969, there's a very real chance

he lived to see old age. He might have stood

in line behind you at the grocery store. He might

have been the quiet, unassuming grandfather leaving three houses down,

the one who always smiled and waved when you went

to get the mail. He might have sat in a

rocking chair on his porch, watching the sun go down,

knowing that he had completely outsmarted the entire world. Knowing

that his true name was sitting in a police evidence locker,

written in thirteen little symbols that no one on earth

was smart enough to read. So you see, some mysteries, friends,

are locked away in the ancient dirt. But the Zodiac,

oh no. He locked his mystery in the ink of

a felt-tip pen, and then he just walked away into

the dark. So, make sure you lock your doors tonight, please.

And don't look too close at the shadows in the

corners of the room. Because sometimes, it's best not to know.

What's hiding in the dark?

This transcript was automatically generated by the podcast creator and may contain errors. Aggregated via the PodcastIndex API.