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



(created by), | 1 more credit »

Watch Now

With Prime Video






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.

Plot Summary | Add Synopsis


See all certifications »


Official Sites:



Release Date:

15 November 1968 (USA)  »

Company Credits

Show detailed on  »

Technical Specs


Sound Mix:


Aspect Ratio:

1.33 : 1
See  »

Did You Know?


This was the only appearance of the Tholians in the "Star Trek" franchise until Star Trek: Enterprise: Future Tense (2003) 35 years later. See more »


The first shot of Chekov in the Defiant's engineering room shows him bobbing back and forth unnaturally, because the film was rolled backward and forward a few times as filler. See more »


[speaking over communicators aboard the USS Defiant]
Dr. McCoy: What the devil!
Capt. Kirk: Bones, what is it? - Bones, what is it? Answer me! - Answer me!
Dr. McCoy: Jim, this ship is dissolving. My hand just passed through a man and a table.
See more »


Featured in William Shatner's Star Trek Memories (1995) See more »

Frequently Asked Questions

This FAQ is empty. Add the first question.

User Reviews

Space Madness and the Punctual Tholians
4 February 2007 | by (United States) – See all my reviews

The Enterprise enters a region of space where space itself phases in and out. Another starship, the Defiant, and her crew have already fallen victim to this spatial malady. Kirk beams over to the shifting Defiant with Spock, McCoy and Chekov; we get to see the crew wearing funky spacesuits in this one. In an eerie sequence of scenes, we see that the Defiant's crew appears to have killed each other. This shifting space also affects the brains of humans, causing a degeneration into insanity. These and later scenes recall the bouts of insanity in "Is There in Truth no Beauty?" earlier this same season. Unfortunately, Kirk should have left Chekov on the Enterprise; Scotty is able to beam back only 3 of them at a time and the Defiant fades away before they can get Kirk back - he's gone, all the way gone (there's something about the number 3 on this show). They even hold a funeral service for Kirk later; yes, this is Kirk's final episode...just kidding. Then the Tholians show up. They're territorial and want the Enterprise outta there!

Like about half of the 3rd season episodes, this is saddled with a snail pace in spots, but the alien Tholians almost make up for this. While we were still seeing actors in lame appliances 20 and 25 years later on the later series (TNG, DS9, etc.) to display alien reps, here we see a truly innovative attempt at visualizing an alien race, complete with an unusual audio signature. You won't soon forget the Tholians. Their energy web - well, that's another matter: seems to me this tactic would work only if an enemy vessel sat unmoving for an hour or two, not using its weaponry. How often does that happen? This episode is also unusual in that Kirk shows up only in the pre-credits scenes, the first act and then disappears until the last 5 minutes (not counting his shots as a ghost). Hence, we observe a new group dynamic shifting into place to fill in the gap: Spock & McCoy further their tense relationship, while Scotty moves in to complete a new trinity. There's an interesting scene with the trio in Spock's quarters near the end, just before final maneuvers are to be made and Scotty walks off with obvious plans to get drunk.

13 of 18 people found this review helpful.  Was this review helpful to you?

Message Boards

Recent Posts
The.Last Star Trek Show timmytony80
Most hated villain? mckee_d
Guy Williams McCartney42
City On The Edge Of Forever timmytony80
Interracial Kiss--Good or Bad? shermandemetrius
The Military, Vietnam timmytony80
Discuss The Tholian Web (1968) on the IMDb message boards »

Contribute to This Page

Create a character page for: