X Minus One was an American half-hour science fiction radio drama series that was broadcast from April 24, 1955, to January 9, 1958, in various timeslots on NBC. It was known for high production values and for adapting stories from the leading American authors of the era, including Isaac Asimov, Ray Bradbury, Philip K. Dick, Robert A. Heinlein, Arthur C. Clarke, and Frederik Pohl.The show's opening sequence was a countdown to blastoff, ending with the line "X minus one... Fire!" This was followed by an introduction by the narrator, who would typically say something like: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, in cooperation with Street & Smith, publishers of Astounding Science Fiction presents... X Minus One.

The show's episodes were typically suspenseful and thought-provoking, exploring themes such as space travel, artificial intelligence, and the nature of reality. Some of the most popular episodes include:

• "The Green Hills of Earth" by Robert A. Heinlein
• "No Contact" by George Lefferts
• "The Parade" by George Lefferts
• "Mars is Heaven" by Ray Bradbury
• "The Caves of Steel" by Isaac Asimov
• "The Cold Equations" by Tom Godwin
• "The Last Question" by Isaac Asimov
• "The Hitchhiker" by Lucille Fletcher
• "The Monsters of the Midway" by Ray Bradbury
• "Nightfall" by Isaac Asimov
• "The Martian Chronicles" by Ray Bradbury

X Minus One was a critical and commercial success, and it is considered to be one of the finest science fiction radio series ever produced. It was canceled in 1958, but it has since been revived several times, and its episodes are still popular today.If you are interested in science fiction, or in old time radio shows, I highly recommend checking out X Minus One. Its episodes are available for download online or on satellite radio.