Star Trek (1966–1969)
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The Tholian Web 

With Capt. Kirk and the derelict USS Defiant apparently lost, the Enterprise grapples with an insanity causing plague and an attack by the Tholians.



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Episode complete credited cast:
Sean Morgan ...
Lt. O'Neil


Kirk and the derelict starship Defiant vanish into a spatial interphase between universes. To rescue him, Spock must maintain position despite a growing, violent hysteria aboard the Enterprise, like that which destroyed the Defiant's crew, as well as a force field being laid around the Enterprise by Tholian patrol ships. Written by Tom D.

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TV-PG | See all certifications »


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Release Date:

15 November 1968 (USA)  »

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Aspect Ratio:

1.33 : 1
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Did You Know?


No insignia was created for the Defiant crew's tunics; however, in creating "In a Mirror, Darkly", the wardrobe department came up with something new: "a variation on the standard Starfleet arrowhead, tilting it and adding an extra angle to its shape." In the original TOS episode, some Defiant crew members may be seen wearing the Enterprise assignment badge. See more »


It's obviously a stand-in for Scott, and not James Doohan, whom the mad crewman jumps down upon in the Engine Room. See more »


Chekov: I don't understand what's so special about this region of space.
Mr. Spock: Picture it this way, Mr. Chekov: we exist in a universe which co-exists with a multitude of others in the same physical space. At certain brief periods of time, an area of their space overlaps an area of ours. That is the time of interphase, during which we can connect with the Defiant's universe.
Uhura: Mr. Spock? We WILL be able to retrieve the Captain at that time... won't we?
Mr. Spock: Yes. However, the dimensional structure of each universe ...
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Featured in William Shatner's Star Trek Memories (1995) See more »

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User Reviews

That's Some Web, That Tholian Web!
5 May 2014 | by (United States) – See all my reviews

This is a great episode. It has all the really cool elements. It has a worthy adversary, the Tholians. It has Kirk caught somewhere between his physical being and his molecules spread across the universe. It has McCoy viciously attacking Spock and his decisions, time after time, questioning his very integrity. Meanwhile, the space they are in has destroyed an entire crew of another ship and is affecting the Enterprise crew. Oh, yes, the Tholians, who are ticked because Spock fired phasers at them, are building a web to tie the Enterprise up for eternity. All these plot elements are interconnected and eventually come to a head. There were certainly some very good episodes in the third season and this is one of them. It's also intriguing how McCoy can be so cruel (almost racist) to Spock but never offers anything of any use to solve the problems. Of course, in this one he is suffering a bit of space sickness. Anyway, they are an interesting pair.

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