Listen to this episode of Decoder Ring:

Get More Decoder Ring Slate Plus members get extended, ad-free versions of our podcasts—and much more. Sign up today and try it free for two weeks. Join Slate Plus Subscribe to Decoder Ring Copy this link and add it in your podcast app. copy link copied! For detailed instructions, see our Slate Plus podcasts page.

Listen to Decoder Ring via Apple Podcasts, Overcast, Spotify, Stitcher, or Google Play.

Decoder Ring is a podcast about cracking cultural mysteries. Every month, host Willa Paskin, Slate’s TV critic, takes on a cultural question, object, idea, or habit and speaks with experts, historians and obsessives to try and figure out where it comes from, what it means and why it matters.

On the early internet, a conspiracy theory known as Ong’s Hat flourished. It combined real physics, speculative science, mysticism, and radical politics, to tell a tale about a secret cult of interdimensional travelers. Throughout the 1990s and early 2000s, clues would emerge about the travel cult: brochures, book catalogs, mysterious interviews, buried artifacts, and more. For years, users worked together to solve the mystery of Ong’s Hat and the man who masterminded it all.

Decoder Ring talks to those seekers and the man behind the curtain, to find out the truth: What is Ong’s Hat?

Download the art for this episode.

Links and further reading on some of the things we discussed on the show:

• Michael Kinsella’s book about Ong’s Hat: Legend-Tripping Online: Supernatural Folklore and the Search for Ong’s Hat

• “Interdimensional Portal” on YouTube

• Audiobook version of The Incunabula Papers

• Scans of the original Ong’s Hat mail-art

• Joseph Matheny’s website

• Joseph Matheny’s interview on Coast to Coast AM﻿

• Download the interactive ebook version of The Incunabula Papers

• Jesse Walker’s book: The United States of Paranoia: a Conspiracy Theory

Email: decoderring@slate.com

Twitter: @willapaskin

This episode was co-written and edited by Willa Paskin and Benjamin Frisch. Benjamin Frisch produced the episode.