Star Trek (1966–1969)
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The Lights of Zetar 

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A mysterious, twinkling mass of sapient energy ravages an important archive and Scotty's new girlfriend may be linked to it.


Herbert Kenwith (as Herb Kenwith)


Gene Roddenberry (created by), Jeremy Tarcher | 2 more credits »





Episode complete credited cast:
William Shatner ... Capt. Kirk
Leonard Nimoy ... Mr. Spock
DeForest Kelley ... Dr. McCoy
Jan Shutan Jan Shutan ... Lt. Mira Romaine
James Doohan ... Scott
George Takei ... Sulu
Walter Koenig ... Chekov
Nichelle Nichols ... Uhura
Majel Barrett ... Nurse Chapel
John Winston John Winston ... Lt. Kyle
Libby Erwin Libby Erwin ... Technician
Rest of cast listed alphabetically:
Barbara Babcock ... Zetar (voice)


The Enterprise is on course to install new equipment on Memory Alpha, the central library storage facility for the Federation. Chief Engineer Scott has been working closely on the project with Lieutenant Mira Romaine with whom he has been forming a romantic attachment. The Enterprise encounters a space storm that kills the staff at Memory Alpha and possesses Lieutenant Mira Romaine. Written by laird-3

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TV-PG | See all certifications »


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Release Date:

31 January 1969 (USA) See more »

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Did You Know?


Final appearance on the show by John Winston as Kyle, though he would return to play the role in Star Trek II The Wrath Of Khan. In addition, the last episode to feature all seven of the regular characters as well as both Kyle and Chappel. See more »


Lt. Romaine has a cold sore on her lower lip that comes and goes between scenes. See more »


Mr. Spock: There is an identity of minds taking place between the alien beings and the mind of Lt. Romaine. Their thoughts are becoming hers.
See more »

Alternate Versions

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


Referenced in Star Trek: Starship Creator (1998) See more »

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User Reviews

My Ship is Being Pursued by Lights in Space!
7 March 2007 | by BogmeisterSee all my reviews

Here it is: the most forgettable Trek episode of the entire 3-year run of the original series. I've seen it a few times over the past 30 years and the only image I could remember until now were these lights flashing in the eye of the female lieutenant, newly-assigned to the Enterprise and the object of Scotty's desires. There are a couple of mildly-amusing scenes of Scotty mooning or swooning over this Lt. Romaine but, otherwise, there's nothing else to elicit even a modicum of interest. Other really low-rated episodes of the 3rd season, such as "Spock's Brain" and "The Way to Eden," at least have that campy ridiculous tone to fall back on or the cheese factor which can be appreciated in our weaker moments. Other boring 3rd season episodes still have some moderately interesting ideas straining to grab our attention, however weakly. Not in this one. This one is just consistently dull throughout - interminably dull, genuinely sleep-inducing - the 'watching grass grow'-type of dull.

The plot has the Enterprise heading towards Memory Alpha, a planetoid functioning as a central library for the entire Federation. This is really the only idea presented here - a galactic library of the future. This concept is soon wrapped up unceremoniously when the library is wiped out by these Lights of Zetar. The Zetar Lights leave, then they return (these are literally flashing points of light). They chase down the Enterprise. They infect Lt. Romaine somehow. She opens her mouth and strange noises come out, like she's about to vomit. The Zetar Lights leave again, then they follow the ship some more. Kirk does decide to fire phasers soon and, you may think, OK, the action is kicking in finally, but he has to stop when Scotty starts crying on the intercom. The top officers sit down with Romaine in the conference room and have a long discussion. The end of this scene, when Kirk explains their final strategy, does contain Shatner's worst acting moment of the series ("If.. we ...can...CONTROL! ..that moment!" accompanied by an odd hand gesture). Oh, yes, there is one nearly-exciting moment when Sulu informs Kirk that...the lights are changing their velocity! Monotony - thy name is Zetar.

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