Archive #002 mails September 15 · Subscribe by August 31 to receive the first file
Case File · Mysteries by Mail

You weren't supposed to find this.

A sealed case file arrives in your mailbox every month. Urban legends. Unsolved cases. Strange history. One complete mystery you don't just read, you solve. On paper, by mail, the way secrets are supposed to travel.

Inside Archive #002: the The Bridgewater Triangle case file. Newspaper, postcard, stickers, and Field Kit.
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Contents of File

Every archive is different.
Here's what never changes.

Archive #001, the Mothman, was our founding case and now lives in the Past Archives. From #002 on, the lineup sits on the docket and can shift with member votes, but each case file stays sealed until it reaches your mailbox. Here is what never changes:

Always

One Complete Story

The month's mystery in full. A long-format story that walks you through the case from the first sighting to the final unanswered question. No cliffhangers held hostage, no homework.

Always · Interactive

The Field Kit

Every file hides a coded transmission and a Field Kit to crack it. Find five clues in the story, build the cipher key, and decode the message by hand. No app, no screen, just you and a pencil.

Always · Season-long

The Season Cipher

Solve a file and you earn one fragment of a year-long cipher. Collect all twelve across the season and they spell your Keeper's Code, a members-only reward for the ones who finish.

Always

Evidence You Can Hold

Paper, ephemera, and artifacts tied to the case, sealed in an envelope and delivered by actual mail. What's inside depends on where the case leads. A haunting doesn't leave the same evidence as a disappearance.

Always

Made for the Mailbox

No boxes, no porch pile-up. Each archive arrives flat and sealed, by real mail. The one envelope this month you'll actually want to open.

Always

The Clue to the Next Case

The docket is public but never final, and members vote on wildcards. Every archive hides a clue to what's coming, and you argue theories and find out together when the next file lands.

After Archive #001, the trail goes dark. Follow the clues.

Now Declassifying

Archive #002: The Bridgewater Triangle

File No. MA-002 · September 2026

Two hundred square miles where everything happens at once.

Two hundred square miles of Massachusetts where ghost lights, black dogs, giant birds, and things with no name all share one address. Colonial curses, a haunted swamp, and a modern police record that will not stay quiet. The full file arrives sealed, with a Field Kit to decode and a verdict to reach. Then we want to hear your theory.

Mails September 15 · Subscribe by August 31
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Frequently Interrogated

Questions from the field

What exactly will I receive?

For Archive #001, everything, because it's an open file shown in full as our first case. From Archive #002 onward, you'll see the tentative lineup on the docket, but the case file itself stays sealed until it arrives: one complete story, physical materials tied to the case, a coded Field Kit you solve by hand, and a hidden clue pointing to the next mystery.

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Eerie, not gory. Think candlelight and old newspapers, not crime-scene photos. We cover real unsolved cases with care and keep the tone curious, never exploitative.

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A new archive mails on the 15th of every month. Subscribe by the last day of the month to secure the current file; join after the cutoff and your membership begins with the next archive. The countdown on this page always shows the current deadline.

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Is this a game I have to solve?

There's no homework and no deadlines, but yes, there's a real puzzle if you want it. Each file hides a coded transmission and a Field Kit that walks you through cracking it by hand, one pencil and five clues. Solve it and you earn a fragment of the season cipher. Prefer to just read? The full story stands on its own, and you can play at your own pace.

The next file is already being assembled.

Archive #003: The Zodiac Killer (tentative) · Declassifies October 2026

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