Hidden in plain sight

Many people have noticed that words can be found among the symbols in the Zodiac killer’s cryptograms without performing any substitutions. Here are some examples from the 340:



Looks a lot like “ZODIAC”




BOO is seen three times

BOY is found twice

Five occurrences of BY, resembling the Halloween card

And here are some words easily found in the 408:

PIG found twice

Tom Voigt’s suspect



BOY found in both ciphers

GOD (or DOG) appears in both ciphers

More occurrences of BY

Are these messages intentional? I don’t think so, with the possible exception of “ZODAIK”. But I thought pi’s recent post about finding Halloween Card references in the 340 cipher was interesting. After performing some simple manipulations of the cipher text, he found a reference to “4-TEEN”:


You can also find the phrase “ROUTE CIPHER” depending on how you interpret the symbols:

Can we find more words in the cipher text by using these “relaxed” rules? For example, let’s allow symbols to be interpreted as different letters based on how they are rotated or flipped. And let’s allow words to wander in different directions, as long as the letters are next to each other.

Developing an algorithm to do this was an appealing amusement to me. Not surprisingly, the algorithm found numerous words in the 340, even without manipulating the grid layout. Here are some examples, each showing where the word appears, and how its symbols are interpreted:

British version of pentobarbital, a sedative also used for euthanasia and lethal injection.

Evil facial hair?

He purportedly called Nancy Slover from a phone booth…

He said he’d give his identity

Peek a boo, you are doomed.

“Hey pig doesnt it rile you up to have your noze rubed in your booboos?”

Suspect Arthur Leigh Allen

Suspect Ted Kaczynski?

A prophetic reference to Tom.

Zodiac said he would blow up a school bus

…with a blast…

…from a bomb.

Yes – we’re still trying and failing.

“When I die I will be reborn in paradice.”

“The Mt. Diablo Code concerns Radians & # inches along the radians”

No Mount Diablo, but a devil can still be found.

Possible victim Donna Lass.

He certainly is one.

Permitting the substitution for the gun target symbol, another misspelling of Zodiac can be found.

Using the same approach, we can find many words hidden in the 408:

Another hidden Zodiac…

A neurotoxin with no antidote

More bomb obsession.

The Unabomber appears yet again.

Arthur Leigh Allen again.

Our pal Tom makes another appearance.


Avid surfer? Or a cop reference?

A Game of Thrones reference, long before its time.

Blaine Blaine tips his hand…

Zodiac’s favorite opera.

Might explain his actions…

These examples were just a tiny sampling of the possible words. The algorithm found around 11,000 words in the 340, and 13,000 words in the 408. It finds so many because of how relaxed our word-finding rules are. To make this even clearer, take the 340, and randomly shuffle its symbols like a deck of cards. Here’s an example:

Here’s a sample of words found in the shuffled cipher by the same algorithm:

Two Zodiac references right off the bat.

Just can’t get away from this guy…

…and his suspect.

Even Allen appears again.

Click here to see the full list of words.

Our relaxed rules produced a cornucopia of words. Claiming that any of the words were intentionally placed would require stronger evidence. So, perhaps this was a meaningless pursuit. But I found it to be a fun programming exercise. We don’t stop making our little sand castles, even though they wash away with the tides.