Star Trek (1966–1969)
36 user 9 critic

The City on the Edge of Forever 

When a temporarily insane Dr. McCoy accidentally changes history and destroys his time, Kirk and Spock follow him to prevent the disaster, but the price to do so is high.



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Episode complete credited cast:
John Winston ...
Bart La Rue ...
Guardian (voice) (as Bartell La Rue)


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 KGF Vissers

Plot Summary | Plot Synopsis


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Release Date:

6 April 1967 (USA)  »

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Technical Specs


Sound Mix:


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Aspect Ratio:

1.33 : 1
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Did You Know?


In one scene in this episode, a poster can be seen advertising a boxing event at Madison Square Garden featuring "Kid McCook" vs. "Mike Mason". For Star Trek: Deep Space Nine: Past Tense: Part 2 (1995), scenic artists Doug Drexler and Michael Okuda created a near replica of this boxing poster for a scene set in 1930 San Francisco; the DS9 poster features the same boxers, and says that it is "their first rematch since Madison Square Garden". See more »


Kirk and Spock run down a 21st Street in Manhattan that curves; the real West 21st and East 21st Streets do not. See more »


Dr. McCoy: Assassins! Murderers! Murderers! Assassins!
[he spots a homeless man]
Dr. McCoy: You! What planet is this?
[the homeless man runs away]
Dr. McCoy: [chasing after him, shouting crazily] No! Don't run! I won't kill you! It's *they* who do the killing! Don't run! I won't kill you!
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Crazy Credits

The closing credits are set against a combination background of stills from that episode and previous episodes. See more »


Referenced in Frasier: Star Mitzvah (2002) See more »


Theme From Star Trek
Written by Alexander Courage
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User Reviews

Arguably, the best episode of the original series
8 December 2013 | by (United Kingdom) – See all my reviews

I love this episode and although I have seen it countless times over the years, I never fail to be impressed by the quality of the story, the acting, even the appropriate music.

I think DeForrest Kelly in particular gives an outstanding performance, suffering from madness due to the accident with the hypo.

I think it's the ending that gets to me every time I watch it! It's the grim inevitability of the climax that is so powerful.

It's a shame that the story lines in more of the "Trek" episodes weren't of this high standard, maybe they wouldn't have canned it after only 3 seasons!

6 of 8 people found this review helpful.  Was this review helpful to you?

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