The story was already set, according to press reports, with "Variety" claiming that Bert I. Gordon had already completed the script. Press sources noted that the studio was clearly attempting to cash-in on the science fiction movie craze. However, the final screenplay is credited to Fred Freiberger (a veteran writer of B movies) and Lester Gorn. The screen story bears a striking resemblance to the 1904 H. G. Wells novel "The Food of the Gods and How It Came to Earth" (Gordon would adapt this novel twice more, once for Embassy Pictures in 1965's "Village of the Giants" and again for American International Pictures in 1976's "The Food of the Gods").