X minus one was effectively the return of Dimension X, and although the opening sequence was revamped and the announcer became Fred Collins, the stories were still as bizarre and intriguing as its predecessor. The first X minus one shows used scripts from Dimension X, but soon created new shows, employing the talents of many great sci–fi authors, including staff writers Ernest Kinoy and George Lefferts, Asimov, Bradbury and Heinlein.
From the far horizons of the unknown come transcribed tales of new dimensions in time and space. These are stories of the future, adventures in which you'll live in a million could–be years on a thousand maybe worlds. The National Broadcasting Company, in co–operation with Street and Smith, publishers of Astounding science fiction magazine, presents....X minus one.....
The series was cancelled after the 126th broadcast on January 9th, 1958. However, the early 1970s brought a wave of nostalgia for old time radio; an experimental new episode was created in 1973, "The Iron Chancellor" by Robert Silverberg, but it failed to revive the series. NBC also tried broadcasting the old recordings, but their irregular once-monthly scheduling kept even devoted listeners from following the broadcasts.