During 1943, Shaver wrote a letter to
Amazing Stories magazine. He claimed to have discovered an ancient language he called "Mantong", a sort of
Proto-Human language that was the source of all Earthly languages. In Mantong, each sound had a hidden meaning; by applying this formula to any word in any language, one could decode a secret meaning to any word, name or phrase. Editor Ray Palmer applied the Mantong formula to several words, and said he realized Shaver was on to something. According to Palmer (in his autobiography
The Secret World), Palmer wrote back to Shaver, asking how he had learned of Mantong. Shaver responded with an approximately 10,000-word document titled "A Warning to Future Man". Shaver claimed to have worked in a factory where, in 1932, odd things began to occur. As Bruce Lanier Wright notes, Shaver "began to notice that one of the
welding guns on his job site, 'by some freak of its coil's field atunements', was allowing him to hear the thoughts of the men working around him. More frighteningly, he then received the telepathic record of a torture session conducted by malevolent entities in caverns deep within the earth." According to
Michael Barkun, Shaver offered inconsistent accounts of how he first learned of the hidden cavern world, but that the assembly line story was the "most common version". Shaver wrote of extremely advanced prehistoric races who had built cavern cities inside the Earth before abandoning Earth for another planet due to damaging radiation from the Sun: an example of a
cryptoterrestrial hypothesis. Those ancients also abandoned some of their own offspring here, a minority of whom remained noble and human, "Teros", while most degenerated over time into a population of mentally impaired
sadists known as "Deros"—short for "detrimental
robots". Shaver's "robots" were not mechanical constructs, but were robot-like due to their savage behavior. These Deros still lived in the cave cities, according to Shaver, kidnapping surface-dwelling people by the thousands for meat or torture. With the sophisticated "
ray" machinery that the great ancient races had left behind, they spied on people and projected tormenting thoughts and voices into our minds (reminiscent of schizophrenia's "influencing machines" such as the
air loom). Deros could be blamed for nearly all misfortunes, from minor "accidental" injuries or illnesses to airplane crashes and catastrophic natural disasters. Women especially were singled out for brutal treatment, including
rape, and
Mike Dash notes that "Sadomasochism|[s]ado-masochism was one of the prominent themes of Shaver's writings". Though generally confined to their caves, Shaver claimed that the Deros sometimes traveled with
spaceships or
rockets, and had dealings with equally evil
extraterrestrial beings. Shaver claimed to possess first-hand knowledge of the Deros and their caves, insisting he had been their prisoner for several years. Palmer edited and rewrote the manuscript, increasing the total word count to a novella length of 31,000. Palmer insisted that he did not alter the main elements of Shaver's story, but that he only added an exciting plot so the story would not read "like a dull recitation". The issue sold out, and generated quite a response: Between 1945 and 1949, many letters arrived attesting to the truth of Shaver's claims (tens of thousands of letters, according to Palmer). The correspondents claimed that they, too, had heard strange voices or encountered denizens of the
Hollow Earth. One of the letters to
Amazing Stories was from a woman who claimed to have gone into a deep subbasement of a
Paris, France building via a secret
elevator. After months of rape and other torture, the woman was freed by a benevolent Tero. Another letter claiming involvement with Deros came from
Fred Crisman, later to gain notoriety for his role in the
Maury Island Incident and the
John F. Kennedy assassination. "Shaver Mystery Club" societies were created in several cities. The controversy gained some notice in the mainstream press at the time, including a mention in a 1951 issue of
Life magazine. Palmer claimed that
Amazing Stories magazine had a great increase of circulation because of the Shaver Mystery, and the magazine emphasized the Shaver Mystery for several years. Barkun notes that, by any measure, the Shaver Mystery was successful in increasing sales of
Amazing Stories. There was disagreement as to the precise increase in circulation, but Barkun notes that reliable sources reflect an increase in monthly circulation from about 135,000 to 185,000. Dash writes that the "critics of the 'Shaver Mystery' were quick to point out that its author was suffering from several of the classic symptoms of
paranoid schizophrenia, and that many of the letters pouring into
Amazing recounting personal experiences that backed up the author's stories patently came from the sorts of people who would otherwise spend their time claiming that they were being persecuted by invisible voices or their neighbor's dog". During 1948,
Amazing Stories ceased all publication of Shaver's stories. Palmer would later claim the magazine was pressured by sinister outside forces to make the change; science fiction fans would credit their boycott and letter-writing campaigns for the change. The magazine's owners said later that the Shaver Mystery had simply run its course and sales were decreasing. The Shaver Mystery Clubs had surprising longevity: Representatives of a club discussed the Shaver Mystery on
John Nebel's popular radio show several times through the late 1950s. Nebel said he thought the discussion was entertaining, but in extant recordings he was also skeptical about the entire subject. Even after the pulp magazines lost popularity, Palmer continued promoting the Shaver Mystery to a diminishing audience via the periodical
The Hidden World. Lanier describes the magazine as "Shaver in the raw" with little of Palmer's editing. Shaver and his wife produced the
Shaver Mystery Magazine irregularly for some years. ==Rock books==