Rod Serling grew frustrated with network and sponsor censorship of his earlier TV plays; for example, the line 'Got a match?' was cut from 'Requiem for a Heavyweight' because the sponsor sold lighters, and Ford once had the Chrysler Building removed from a skyline shot.

Serling's 1956 script 'Noon on Doomsday' was originally a direct commentary on the murder of Emmett Till, but was progressively watered down by the network, moving it out of the South and changing the victim to a Jewish pawnbroker and finally just a foreigner in an unnamed town.

Serling realized that a science-fiction setting would let him tackle controversial themes with less network interference, leading him to write 'The Time Element,' a 1957 time-travel pilot script about a man trying to warn people about the attack on Pearl Harbor; it was initially rejected and shelved before being produced in 1958 for Desilu Playhouse, whose success paved the way for The Twilight Zone.

When the show's future looked shaky after its first season, CBS reportedly considered replacing Serling with a more prestigious host and even offered the job to Orson Welles, who turned it down.

To cut costs in season two, new CBS executive James Aubrey ordered six episodes to be shot on videotape instead of film; because tape editing was nearly impossible at the time, these episodes had to be shot live-style with four cameras on a soundstage, severely limiting location shooting, and the experiment only saved about $6,000 per episode before being abandoned.

For its fourth season, the show was expanded from a half-hour to an hour format to fill the time slot of the sitcom Fair Exchange, a change Serling strongly disliked, fearing viewers wouldn't know if they were watching Twilight Zone or a soap opera.

Actor Robert McCord holds the record for most appearances on the series, appearing in 32 episodes, almost all in uncredited roles, while Jack Klugman, Burgess Meredith, and John Anderson are tied for the most starring roles with four episodes each.

The show's famous guitar-and-bongo theme, used from season two onward, was actually a splice of two separate stock music cues, 'Etrange 3' and 'Milieu 2,' composed by French avant-garde composer Marius Constant as work-for-hire library music, and played by guitarist Howard Roberts.

The fifth-season episode 'An Occurrence at Owl Creek Bridge,' a modified French short film aired on the show, won the Academy Award for Best Short Film in 1963.

The episode 'The Encounter' was pulled from syndication after its initial airing due to its racial overtones and did not air again until Syfy broadcast it in 2016.