Gibson (1897-1985) wrote books on stage magic, hypnotism, and the occult, and ghost-wrote for Houdini, Thurston, and Blackstone before The Living Shadow launched the pulp in April 1931. The radio version from 1937, voiced first by Orson Welles, gave the character his mind-clouding invisibility, absent from the pulps, where he used magician's tricks.
Gibson moved comfortably between skepticism and fascination: he exposed fraudulent mediums with Houdini yet kept writing books on psychic phenomena, numerology, and the unexplained all his life. The Shadow sits exactly on that seam, a debunker's hero who fights with a mystic's methods.
Pulp-era heroes encode the era's obsession with Orientalist mysticism: the radio Shadow learned his powers in the East, a template Mandrake, Doctor Strange, and a dozen successors inherited. Critics read it as colonial fantasy; occult revivalists read it as transmission of real traditions through mass fiction.
When a hero's entire toolkit is escape artistry, hypnotism, and illusion, is he a crime-fighter, or a magician who found a bigger stage?