Star Trek (1966–1969)
35 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


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Release Date:

15 December 1966 (USA) See more »

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Did You Know?


In the James Blish adaptation of this story, presumably based on an earlier draft of the script, Stiles dies. In addition, Robert Tomlinson and Angela Martine actually marry, in a second ceremony late in the story. When the Enterprise fires on the Romulan ship for the final time, the latter explodes immediately, with the conversation between Kirk and the Romulan commander being omitted. See more »


In his initial log entry, Kirk refers to the Romulan home worlds as Romulus and Remus - after the brothers in Rome's founding legend. When Spock displays the star sector map, it shows Romulus and Romii. However, since the names were written in capital letters, it is possible it was meant to be "Rom II", i.e., "Romulus 2", a star chart designation for Remus. See more »


Captain James T. Kirk: He did exactly what I would have done. I won't underestimate him again.
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Alternate Versions

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


Referenced in The Toys That Made Us: Star Trek (2018) See more »


Theme From Star Trek
Written by Alexander Courage
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User Reviews

Enter the Romulans
6 May 2009 | by MaxBorg89See all my reviews

Undoubtedly one of the best episodes ever, Balance of Terror is 45 minutes of well executed suspense, with intelligent real-world parallels (the title refers to a situation very similar to what was going on between the US and the Soviet Union during the Cold War), spot-on characterizations and the introduction of Star Trek's second most important hostile alien race after the Klingons: the Romulans.

After receiving a distress call from a Federation outpost, the Enterprise is dangerously close to the Neutral Zone which, if crossed, would lead to open conflict with the Romulans, although no one has ever actually seen them in the flesh. Soon enough, a Romulan vessel appears, carrying a new weapon and a cloaking device which makes it nearly impossible to defeat. Facing the threat of imminent annihilation, Kirk must engage in a battle of wits with the Romulan Commander (Mark Lenard) to ensure the survival of his crew. Unfortunately, the task is made more difficult when one of the men accuses Spock of being in league with the enemy, due to the physical resemblance between Romulans and Vulcans, two races that are, in fact, distantly related (a fact that is quite ironic with hindsight, given Lenard went on to play Spock's father Sarek starting with Season 2).

Always very critical when it came to the subject of war, Star Trek enjoys one of its finest hours with its most gripping and tense take on the topic. Although the Romulans aren't actually based on the Soviets (the name is actually taken from Romulus, the founder of Rome), the scenario is quite obviously inspired by the very vivid fear American and Russian citizens had at the time that either nation might be able to destroy the other with nuclear weapons (that fear gave birth to the titular concept of "balance of terror"). But even without the subtext, this remains an essential episode, due for the most part to the intellectual battle between the two adversaries, which translates into a thesping duel between Shatner and Lenard. No need to say who wins...

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