Inside the compound where the missing wife of Scientology's leader might be living

David Miscavige, the leader of the Church of Scientology, is one of the most well-known Scientologists in the world. But Miscavige's wife, Shelly Miscavige, hasn't been seen in public since 2006.

The Church of Scientology says that Shelly Miscavige isn't missing, and she hasn't been kidnapped. Instead, Scientology says she has been working inside the church.

The disappearance of Shelly Miscavige continues to be a high-profile mystery for Scientology critics and former members. A 2014 Vanity Fair article referred to Shelly Miscavige as "Scientology's Vanished Queen."

Filmmaker Alex Gibney's 2015 Scientology documentary "Going Clear" passes over the disappearance of Shelly Miscavige, instead focusing on testimonies from former Scientology members and the history of the organisation's founder L. Ron Hubbard.

Steve Hall, a former Scientologist who left the church in 2004 after spending the previous 17 years at its international management level as a senior writer of its marketing materials, spoke to Business Insider about where Shelly Miscavige might be. He thinks Shelly is at Scientology's little-known "Church of Spiritual Technology," a remote forest compound with prison-like security in Twin Peaks, Calif., near San Bernadino.

It's important to note that Shelly Miscavige may not actually be held against her will. Instead, she may have been convinced that she must stay at the remote compound to make up any alleged crimes she may have committed against the Church of Scientology. The 2014 Vanity Fair article says that Miscavige was tasked with restructuring the upper levels of Scientology, but she told a former Scientology at her father's funeral that she had "f----d up."

One person who has visited the compound is "Angry Gay Pope," the nom de guerre of an Anonymous activist who has staged protests against Scientology. In 2010, he took these pictures of the CST compound in Twin peaks, Calif., documenting its spiked fences, razor wire, motion detectors, infrared spotlights, satellite dishes, fuel tanks and mysterious semi-permanent trailers.