Star Trek (1966–1969)
36 user 8 critic

Balance of Terror 

The Enterprise must decide on its response when a Romulan ship makes a destructively hostile armed probe of Federation territory.


Vincent McEveety


Paul Schneider, Gene Roddenberry (created by)

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Episode complete credited cast:
William Shatner ... Capt. Kirk
Leonard Nimoy ... Mr. Spock
Mark Lenard ... Romulan Commander
Paul Comi ... Stiles
Lawrence Montaigne ... Decius
DeForest Kelley ... Dr. McCoy
Grace Lee Whitney ... Yeoman Rand
George Takei ... Sulu
James Doohan ... Scott
Nichelle Nichols ... Uhura
Stephen Mines ... Tomlinson
Barbara Baldavin Barbara Baldavin ... Angela
Garry Walberg ... Hansen
John Warburton ... The Centurion


The Enterprise answers a distress call from Federation Outpost #4, a monitoring station on the Federation side of the neutral zone with the Romulan Empire. The outposts were established over a century ago and no one has actually seen a Romulan. The Romulan vessel seems to have some type of high energy explosive device as well as a cloaking device to make the ship invisible. When it appears that Romulans bear a strong resemblance to Vulcans, Kirk must deal with a rebellious crew member. He must also engage in a dangerous cat and mouse game with a very intelligent Romulan commander. Written by garykmcd

Plot Summary | Plot Synopsis


TV-PG | See all certifications »






Release Date:

15 December 1966 (USA) See more »

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Did You Know?


The viewscreen display shown as the Enterprise approaches the Neutral Zone shows Earth Outposts 1-7 in "Sector Z-6". See more »


While the Enterprise is laying in wait for the Romulan ship, both crews are whispering, and trying to make no other noises. As there is no sound transmission in space, this would seem to be unnecessary. However, in the future depicted the same equipment that can detect dust on a planet light years away is likely sensitive enough to detect the hull of a ship vibrating ever so slightly from sounds made within. This element is a "tip of the hat" to submarine war movies such as The Enemy Below, which were the basis for this story. See more »


Stiles: These are Romulans! You run away from them and you guarantee war. They'll be back - not just one ship, but with everything they've got. You know that, Mr. Science Officer. You're the expert on these people, but you've always left out that one point. Why? I'm very interested in why.
Captain James T. Kirk: Sit down, mister.
[Stiles does so, there is an awkward silence]
Mr. Spock: I agree. Attack.
Captain James T. Kirk: Are you suggesting we fight... to prevent a fight?
Dr. McCoy: Based on what? Memories of a war over a century ago? On theories about a people we've...
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Alternate Versions

Special Enhanced version Digitally Remastered with new exterior shots and remade opening theme song See more »


Referenced in After Trek: Si Vis Pacem, Para Bellum (2017) See more »


Theme From Star Trek
Written by Alexander Courage
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User Reviews

Possibly the best Star Trek episode ever
5 December 2006 | by MartinHaferSee all my reviews

Despite all the hoopla about THE TROUBLE WITH TRIBBLES episode, THE BALANCE OF TERROR might just be the best episode of the series. And, while I have always loved A PIECE OF THE ACTION because it is so much fun, I really do have to cast my vote as this Romulan episode as being the very best.

The episode interestingly enough, is really like a WWII submarine movie in that it bounces back and forth between the cloaked Romulan ship and the Enterprise as it seeks to destroy the Romulans before they sneak back across the Neutral Zone after a raid on Federation outposts. In so many ways, the show is much like the film THE ENEMY BELOW--where the American Captain (Robert Mitchum) and the German Captain (Curt Jurgens) are shown in counter-point as they both try to outwit the other--and in the process develop a grudging respect for their foe.

Interestingly enough, the episode is confined to the Enterprise--and this is amazing because an episode on board ship could easily have been static and dull. But, because the writing was so fantastic and the main characters written and acted so well (Shatner and Mark Leonard as the Romulan leader). Overall it's very tense and exciting. Oddly, for the die-hard Trekkers out there, they'll recognize Leonard as the same actor who later played Spock's father.

The bottom line is this is simply a great and extremely engaging episode that will keep you on the edge of your seat.

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