When an accident causes Dr. McCoy to go temporarily insane, he escapes to a strange planet. There, the search party discovers a device left by a superior, vanished civilization, a time portal that plays the history of Earth for them - but then Bones jumps through it into the past, causing a change in history important enough to make the Enterprise vanish. Kirk and Spock, who fortunately made a tricorder recording, must attempt to go through to just before McCoy's arrival and stop him from changing history in the United States during the Great Depression, where they have no advanced technology available. Written by
Did You Know?
When asked in February 26, 1992 interview whether the makers of this episode consciously intended it to have the contemporaneous anti-Vietnam-war movement as subtext, associate producer Robert H. Justman
replied, "Of course we did." See more
The Guardian of Forever first speaks in response to Kirk's questioning of its origin by saying "Then what is it?" by responding "A question." Moments earlier, Kirk had asked the same question in slightly different wording, "What is this thing Mr. Spock?" with no response, though this question was directed to Mr. Spock. See more
[tending to an injured and unconscious Sulu
There's a heart flutter. I'd better risk a few drops of cordrazine.
That's tricky stuff - are you sure you want to risk...
[McCoy administers the cordrazine, and Sulu's eyes open
You were about to make a medical comment, Jim?
Who, me, Doctor?
Script Supervisor is written as "SCPIPT SUPERVISOR...GEORGE A. RUTTER" in the credits. This happened on at least two other episodes in season one. See more
Theme From Star Trek
Written by Alexander Courage See more