23 user 6 critic

Dagger of the Mind 

Kirk and psychiatrist Helen Noel are trapped on a maximum security penal colony that experiments with mind control and Spock must use the Vulcan mind-meld to find a way to save them.


Vincent McEveety


Shimon Wincelberg (as S. Bar-David), Gene Roddenberry (created by)




Episode complete credited cast:
William Shatner ... Capt. Kirk
Leonard Nimoy ... Mr. Spock
James Gregory ... Dr. Tristan Adams
DeForest Kelley ... Dr. McCoy
Morgan Woodward ... Dr. Simon van Gelder
Marianna Hill ... Helen Noel
Nichelle Nichols ... Uhura
Susanne Wasson Susanne Wasson ... Lethe
John Arndt John Arndt ... First Crewman
Larry Anthony Larry Anthony ... Transportation Man
Ed McCready Ed McCready ... Inmate
Eliezer Behar Eliezer Behar ... Therapist (as Eli Behar)


After a psychologically disturbed patient from the Tantalus penal colony, Dr. Simon Van Gelder, manages to escape to the Enterprise, Dr. McCoy begins to suspect that something is amiss on the colony. Captain Kirk and Dr. Helen Noel beam down to the planet to investigate. Written by garykmcd

Plot Summary | Plot Synopsis


TV-PG | See all certifications »






Release Date:

3 November 1966 (USA) See more »

Also Known As:

Dagger of the Mind See more »

Company Credits

Show more on IMDbPro »

Technical Specs


Sound Mix:




Aspect Ratio:

See full technical specs »

Did You Know?


The part of Helen Noel was originally written for Janice Rand. However, the producers wanted to avoid showing Kirk becoming involved with her, and Grace Lee Whitney was already on the verge of leaving the show due to personal problems on the set. Whitney had been sexually assaulted by one of the show's executives at a wrap party. She believes she was pushed out for speaking up in protest of this. In any event, from a dramatic point of view, it made more sense for a trained psychotherapist, rather than a yeoman, to accompany Kirk to the Tantalus rehabilitation colony. See more »


When Kirk was in the neural neutralizer chair. Dr. Adams takes the controls away from Helen Noel. One of Dr. Adams' orders to Kirk is to drop his (Kirk's) phaser, which is done. Then, Kirk is ordered to drop his communicator where Kirk musters the effort to try to contact the Enterprise (which would be futile due to security measures). If Kirk had the energy to call the ship, then he could have used the phaser to shoot the beam emitter for the neutralizer thus breaking its effects on him. See more »


Helen Noel: Dr. Helen Noel, Captain. We've met...
Helen Noel: [Kirk and Spock glance at each other. Without replying, Kirk joins her on the transporter pad] Don't you remember? The science lab Christmas party.
Captain James T. Kirk: Yes, I remember.
Helen Noel: You dropped in...
Captain James T. Kirk: [cuttin her off] Yes, yes, I remember.
Mr. Spock: Problem Captain?
Captain James T. Kirk: [Kirk steps off the transporter pad to talk to Spock] Mr. Spock, you tell McCoy that she had better check out as the best assistant I ever had.
See more »

Alternate Versions

Special Enhanced version Digitally Remastered with new exterior shots and remade opening theme song. A highlight of the new special effects is a new exterior shot of the penal colony, replacing a re-used matte painting from another episode. See more »


Referenced in The Red Shirt Diaries: Dagger of the Mind (2014) See more »


Theme from Star Trek
Written by Alexander Courage
See more »

Frequently Asked Questions

This FAQ is empty. Add the first question.

User Reviews

The Overly-Trusting Kirk
25 April 2014 | by HitchcocSee all my reviews

James Gregory manages a penal colony for the criminally insane. When one of his patients, the former manager, Van Gelder, gets on board the Enterprise. He acts mad, and Kirk doesn't listen to him. Gregory tells Kirk that he is welcome to come to the surface and check out the story that Van Gelder is spouting. Spock, meanwhile, continues to investigate the invader, who doesn't get much more lucid. Kirk insists that a person with great knowledge of the mind go to the surface as well. She is a gorgeous Brunette who is apparently one of the Captain's previous conquest. Dr. Adams (Gregory) shows Kirk and the young woman a machine that scans and corrects brain functions. Kirk falls for the charade and soon finds himself in grave danger, having his own consciousness messed with. We soon find out that the inmates are literally running the asylum. We have to ask why, with all the medical knowledge that should have evolved, people are being treated this way, it begs that question. The gullibility of Kirk gets him in trouble many times during this series and this is another time when his judgment is respected.

5 of 8 people found this review helpful.  Was this review helpful to you? | Report this
Review this title | See all 23 user reviews »

Contribute to This Page

Free Movies and TV Shows You Can Watch Now

On IMDb TV, you can catch Hollywood hits and popular TV series at no cost. Select any poster below to play the movie, totally free!

Browse free movies and TV series

Stream Trending Movies With Prime Video

Enjoy a night in with these popular movies available to stream now with Prime Video.

Start your free trial

Recently Viewed