Because of the great effort involved in writing two full-length novels every month, several guest writers were hired to write occasional installments in order to lighten Gibson's workload. Those guest writers included Lester Dent, who also wrote the Doc Savage stories, and Theodore Tinsley. In the late 1940s, mystery novelist Bruce Elliott (also a magician) temporarily replaced Gibson as the primary author of the pulp series. Richard Wormser, a reader for Street & Smith, wrote two Shadow stories. For a complete list of Street and Smith's Shadow novels, see the List of The Shadow stories article.