A group of children on the distant Federation outpost Triacus are possessed by an evil spirit that convinces them to kill their parents and then commandeer the Enterprise.


The Enterprise arrives to investigate occurrences on the Federation outpost Triacus, where Captain Kirk discovers all of the people on the outpost have mysteriously committed mass suicide. Even more oddly, the group of children on Triacus seem totally oblivious to the event, continuing to play games as if nothing has happened. Kirk has the children beamed aboard the Enterprise, where they react with hostility to any questioning about what happened to their parents. When the children are left to themselves, they chant and an ancient alien claiming to be an angel appears, congratulating them on their good work for getting rid of the adults on Triacus and telling them that they must take control of the Enterprise and make way for Marcos XII. The children, with the alien's help, are able to exercise psychological control over adults. With this they manage to make Sulu, Chekov, Uhura, Scotty, several other crewmen, and even Spock for a short time go along with their command of the ship, employing various methods. For example, at first Sulu, Chekov, and Uhura believe that they can see Triacus on the viewscreen, even though they are no longer orbiting the planet; after Kirk makes them realize that this is not true, Sulu believes that they cannot alter course because if they do the ship will be destroyed by the rings of swords they are "flying" through. This comes to a climax when Chekov and two security personnel corner Kirk and Spock, telling them that Starfleet has ordered their arrest; when Kirk resists, Chekov threatens to shoot him. Luckily, they are able to subdue the delusional men through a few well-placed nerve pinches and some more traditional fighting. Kirk and Spock return to the bridge, where they summon the alien themselves by replaying a recording of the children's chant, and then challenge him. They show the children footage of themselves on Triacus, playing with their parents, and the children suddenly realize what they have done and begin to cry. Without their support, the alien is powerless, and fades away.

Log Entries

"Captain’s log, stardate 5029.5. Responding to a distress call from our scientific colony on Triacus, we are beaming down to investigate."
"Captain’s log, supplementary. We have buried the members of the Starnes exploration party. Everyone has been deeply affected by what has happened here, with some important exceptions."
(The following four entries were recorded by Professor Starnes, stationed on Triacus)
"Log date 5025.3. Ever since our arrival on Triacus, I've felt a certain growing feeling of uneasiness. At first, I attributed it to the usual case of nerves associated with any new project. However, I found that the rest of my associates are also bothered by these... anxieties. The only ones not affected are the children – bless them, find the whole thing an exciting adventure. Ah, to be young again."
"5032.4. The feeling of anxiety we've all been experiencing is growing worse."
"5038.3. Professor Wilkins finished his excavation today. Although whatever civilization that might have been here was destroyed by some natural catastrophe, it would appear that one of the race took refuge in the cave. For our efforts, we are becoming even more apprehensive. As if some unseen force were influencing us..."
"I'm being influenced to do things that do not make sense. I even went so far as to call Starfleet Command, to request a spaceship to be used as a transport. It was only when I couldn't tell them what I wanted to transport that I began to realize that my mind was being directed. I decided to send a dispatch to Starfleet, warning them. God forgive us, must destroy ourselves! Alien upon us! The enemy from within! The enemy!"

Memorable Quotes

"They're crying Jim. I don't know how it happened but it's good to see."

- McCoy, referring to the children

"What's wrong?"
"I am unable to lock onto the proper coordinates, Captain. It appears we are no longer orbiting Triacus."
"That's impossible. If we're not orbiting Triacus... then the men I beamed down... are dead!"
"Captain, we are no longer orbiting Triacus."

- Kirk and Spock

"Scotty. I want you to override the bridge navigation system. Lay in a course for Starbase 4."
"I can't do that, sir!"
"Why not!?"
"These are very sensitive instruments! I will not have you upset their delicate balance! We would all be lost! Forever lost!"

- Kirk and Scotty

"Friends, we have reached a moment of crisis. The enemy has discovered our operation. But they are too late. They no longer control the ship, we do. We shall prevail. They will take us anywhere we desire."

- The Gorgan

"Take Mr. Sulu to his quarters, he's relieved of duty. Mr. Leslie egdirb hte egdirb kcops. Enifnoc mih ot sretrauq... Egdirb kcops morf eht egdirb! I dias... Ekat Rm Ulus ot sih sretrauq... Evomer tnanetueil uruhu and kcops dna enifnoc meht ot sretrauq! Did you hear me? Did you hear me!?"

- Kirk, his speech reversed by Tommy Starnes

"Go away, now. Go away or we'll kill you!"

- Scotty, to Kirk and Spock when they attempt to take over Auxiliary Control

"I forbid it."

- The Gorgan, trying to stop Kirk from showing the children pictures of happy times with their parents

"I've lost command. I've lost the Enterprise."

- Kirk, in the midst of a panic attack while riding with Spock in the turbolift

Background Information

  • The recreation room in this episode was created at great expense and never used again, except in re-dressed form as the arboretum in "Is There in Truth No Beauty?". A scene had been filmed in the room for "Elaan of Troyius", but it was cut from the episode. Roddenberry had plans to create the first holodeck in Star Trek during the third season and to place it in this new set, however, with the problems encountered in the final year, these plans never materialized.
  • Brian Tochi, along with Phil and Iona Morris in "Miri" and Clint Howard in "The Corbomite Maneuver", is one of a very few actors who appeared in TOS as a child and was later cast in one of the new series or movies. Tochi and Pamelyn Ferdin were later reunited on Space Academy, a live-action Saturday morning television series produced by Filmation which aired on CBS from 1977 to 1979.
  • Spock's playback of the children's chant at the end of the episode apparently comes from their chant in the recreation room. The children perform the chant only one other time on screen (on the bridge), but they use "High, High" instead of "Hail, Hail" as the first words in that version.
  • This is the only episode of the original series in which we see the United Federation of Planets flag.
  • It is never explained how Kirk knew the alien, played by Melvin Belli, by the name of Gorgan.
  • The entrance to the Gorgan's cave is seen again in many third season episodes, including "Spock's Brain", "The Cloud Minders", "All Our Yesterdays" and "That Which Survives".
  • In the trailer, footage of Gorgan's transformation at the end of the episode is seen without the "green light bath" special effects.
  • In this episode, two redshirts are beamed into space.
  • During one scene on the bridge, Kirk tries to give orders to Mr. Leslie, but his words are garbled. If the audio for this scene is played in reverse, Kirk can be heard to say, "Remove Lieutenant Uhura and Mr. Spock from the bridge. Confine them to quarters. Did you hear me? Take Mr. Sulu to his quarters. He's relieved of duty. Remove Lieutenant Uhura and Mr. Spock from the bridge. Confine them to quarters. Take Mr. Sulu to his quarters, I said. (garbled) Mr. Spock from the bridge. Confine him to quarters. Mr. Leslie, take Mr. Sulu to his quarters. He's relieved of duty." Listen to Kirk's orders ungarbled file info
  • Professor Starnes and his colleagues apparently were of stronger constitutions than the members of the Enterprise crew who were affected by the Gorgan and/or the children. Starnes said he had requested a transport ship, presumably to remove his entire party to Marcos XII, but then couldn't remember what he wanted to transport. Thus, his request was apparently denied, and he decided to send off a warning dispatch to Starfleet, proving Spock's observation that Starnes had finally recognized the Gorgan and begun fighting its influence. Although Spock says Starnes' dispatch was never sent, the Enterprise came to Triacus in response to a distress call which must have been placed by Starnes.
  • During the scene in the transporter room after the security detail has been beamed into space, Spock turns on the bridge view screen monitor. As his hand drops to his side, it passes behind the image of the stars because of the special effect, rather than in front of it. It is only visible in a few frames, however, and barely noticeable when viewed in real-time.

Production Timeline

Video and DVD releases

Links and References

Main cast

Guest Stars

Uncredited Co-Stars


Auxiliary Control; cyalodin; Epsilon Indii; Friendly Angel; food synthesizer; ice cream; Lacunar amnesia; Marcus XII; Starbase 4; Starnes Exploration Party; suicide; "Ring Around the Rosie"; Triacus; Triacus marauders; United Federation of Planets; Wilkins

External links

Previous episode produced:
"The Enterprise Incident"
Star Trek: The Original Series
Season 3
Next episode produced:
"Spock's Brain"
Previous episode aired:
"The Paradise Syndrome"
Next episode aired:
"Is There in Truth No Beauty?"
Previous remastered episode aired:
"The Immunity Syndrome"
TOS Remastered Next remastered episode aired:
"All Our Yesterdays"
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