X Minus One (1955-1958) was a half-hour OTR science fiction drama series with episodes featuring adaptations of stories by leading science fiction writers. Cast varied by episode. X Minus One is significant because it is acknowledged as the best science fiction anthology radio show. The first fifteen episodes of the series series were revived from Dimension X, broadcast on National Broadcasting Corporation (NBC), 8 April 1950-29 September 1951.
Total Episodes: 125 (estimated from 119 alleged unique scripts)
Surviving Episodes: 129
The first fifteen episodes of X Minus One were revived from Dimension X (8 April 1950-29 September 1951; 50 total episodes, 50 surviving), the first science fiction series with broad adult appeal, featuring works by young science fiction writers like Ray Bradbury, Robert Bloch (Psycho), Robert Heinlein, Isaac Asimov, and Kurt Vonnegut. Notable episodes are Bradbury's "Mars Is Heaven" and "Martian Chronicles."
Continuing with the "X factor"—stories told in future "time and space"—the remaining episodes of X Minus One were new adaptations of fiction written by leading science fiction writers whose stories appeared in Galaxy Magazine. Examples include Isaac Asimov ("Nightfall," "C-Chute," and "Hostess"), Ray Bradbury ("And The Moon Be Still As Bright," "Mars is Heaven," "The Veldt," "Dwellers in Silence," "Zero Hour," "To the Future," "Marionettes, Inc.," and "There Will Come Soft Rains"), Philip K. Dick ("The Defenders" and "Colony"), Robert A. Heinlein ("Universe," "Requim," "The Roads Must Roll," and "The Green Hills of Earth"), George Lefferts ("The Parade"), Fritz Leiber ("A Pail of Air"), J. T. McIntosh ("Hallucination Orbit"), Frederik Pohl ("The Tunnel under the World"), Robert Sheckley ("Skulking Permit"), and L. Sprague de Camp ("A Gun for Dinosaur").
X Minus One was broadcast 24 April 1955 - 9 January 1958, on National Broadcasting Company (NBC). The opening for each episode was distinctive, with the announcer saying,
Countdown for blastoff . . . X minus five, four, three, two, X minus one . . . Fire!
[Rocket launch SFX]
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 may-be worlds. The National Broadcasting Company (NBC), in cooperation with Galaxy Science Fiction Magazine, presents—X-X-X-X—MINUS-MINUS-MINUS-MINUS—ONE-ONE-ONE-one . . .
NBC aired transcriptions (recordings) of X Minus One episodes from 24 June 1973-1975, as an experiment to see whether nostalgia would support radio drama. The once-a-month scheduling was confusing and problematic, and X Minus One died again in 1975.
Episodes of X Minus One at Internet Archive website
Scripts at Generic Radio workshop website
X Minus One radio logs at Jerry Haendiges Vintage Radio Logs website
X Minus One plot summaries and credits at Radio Gold Index website
The Definitive X Minus One at Digital Deli Too website
Dimension X radio logs at Jerry Haendiges Vintage Radio Logs website
Dimension X log by James Widner
The Definitive Dimension X at Digital Deli Too
Dimension X plot summaries and credits at Radio Gold Index website
Episodes of Dimension X at Internet Archive website