118 in the Doc Savage series. A prospector happens upon a black rock in the deesert with explosive properties. When a man the prospector doesn't like seems to be getting ready to use the material, the prospector goes to Doc Savage and his band of men.

Kenneth Robeson was the house name used by Street and Smith Publications as the author of their popular character Doc Savage and later The Avenger. Though most Doc Savage stories were written by the author Lester Dent, there were many others who contributed to the series, including: William G. Bogart Evelyn Coulson Harold A. Davis Lawrence Donovan Alan Hathway W. Ryerson Johnson Lester Dent is usually considered to be the creator of Doc Savage. In the 1990s Philip José Farmer wrote a new Doc Savage adventure, but it was published under his own name and not by Robeson. Will Murray has since taken up the pseudonym and continued writing Doc Savage books as Robeson. All 24 of the original stories featuring The Avenger were written by Paul Ernst, using the Robeson house name. In order to encourage sales Kenneth Robeson was credited on the cover of The Avenger magazine as "the creator of Doc Savage" even though Lester Dent had nothing to do with The Avenger series. In the 1970s, when the series was extended with 12 additional novels, Ron Goulart was hired to become Robeson.