The Dero

The Dero ("detrimental robots") are the malign underground beings of hollow-Earth lore: degenerate descendants of an ancient civilization that abandoned Earth's surface, dwelling in tunnel networks and misusing their forebears' leftover ray machinery to afflict humanity with accidents, madness, and intrusive voices. A benevolent remnant, the Tero, opposes them.

The mythology begins with Richard Shaver, a Pennsylvania welder who wrote to Amazing Stories claiming ancestral memory of the underground world. Editor Ray Palmer published the material as fact beginning in March 1945 ("I Remember Lemuria!"), and "the Shaver Mystery" became a circulation sensation, running for years amid reader letters reporting their own tunnel experiences. Shaver's Titans and Atlans, cavern cities, and ray-torment cosmology built the template.

Shaver claimed direct experience; Amazing Stories readers supplied a wave of copycat testimony. The Dero themselves faded as a reported being, but their infrastructure never did.

The Shaver Mystery is the headwater of underground-base lore: Dulce's levels, tunnel networks under the Southwest, and reptilians-below-us stories all descend from it. Palmer went on to co-found Fate magazine and midwife the flying saucer era, linking the two mythologies personally.

The case is documented publishing history: Shaver had been institutionalized and heard voices, Palmer knowingly packaged disturbed material as revelation for sales, and the "mystery" was contemporaneous scandal even within science fiction fandom, which campaigned against it. Historians treat the Dero as the clearest example of one editor manufacturing a folklore. Hollow-Earth claims themselves fail against basic geophysics. Nothing has ever supported the tunnels.