Dagger of the Mind

"**Dagger of the Mind**"
"Dagger of the Mind"
Star Trek: The Original Series episode
Episode no.	Season 1; Episode 9
Directed by	Vincent McEveety
Written by	S. Bar-David
Featured music	Alexander Courage
Cinematography by	Jerry Finnerman
Production code	011
Original air date	November 3, 1966
Guest appearances
	James Gregory – Dr. Tristan Adams; Morgan Woodward – Dr. Simon van Gelder; Marianna Hill – Dr. Helen Noel; Larry Anthony – Mr. Berkley (credited as Transportation Man); Susanne Wasson – Lethe; John Arndt – Fields (credited as First Crewman); Eli Behar – Therapist Eli; Ed McCready – Inmate; Lou Elias – Therapist Guard; Eddie Paskey – Lt. Leslie; Frank da Vinci – Vinci; Irene Sale;
Episode chronology
← Previous; "Miri"	Next →; "The Corbomite Maneuver"
	Star Trek: The Original Series season 1
	List of episodes

"Dagger of the Mind" is the ninth episode of the first season of the American science fiction television series Star Trek. Written by Shimon Wincelberg (under the pen name "S. Bar-David") and directed by Vincent McEveety, it first aired on November 3, 1966.

In the episode, the Enterprise visits a rehabilitation facility for the criminally insane where the chief doctor has been using a device which destroys the human mind.

This episode introduces the Vulcan mind meld.

The title is taken from a soliloquy by the title character in William Shakespeare's play Macbeth.^[1]

^ Rhiannon Guy; Emma Jones (2005). The Shakespeare Companions. Robson. p. 108. ISBN 978-1-86105-913-0. Retrieved October 20, 2010.

[Comp-1] Rhiannon Guy; Emma Jones (2005). The Shakespeare Companions. Robson. p. 108. ISBN 978-1-86105-913-0. Retrieved October 20, 2010.

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