Shadowed Millions,

Maxwell Grant was a 'house pseudonym' used largely by Walter B. Gibson, though Theodore Tinsley wrote 27 Shadow stories between 1936 and 1943; Lester Dent wrote one story, The Golden Vulture, in 1938; Bruce Elliott wrote 15 Shadow stories between 1946 and 1948; and Dennis Lynds wrote nine Shadow paperback novels between 1964 and 1967. - Wikipedia