Continuity mistake: After Spock's brain is taken McCoy says he has no idea how long the body can last on life support without the brain. Somehow in the following few moments McCoy has established that Mr Spock's Body will die in exactly 24 earth hours. No explanation is given as to how he came up with this figure.
Revealing mistake: "Trek's" new 3rd season uniforms were tighter-fitting than their velour predecessors, presenting a problem for some actors. When the landing party beams down in this episode, the outline of William Shatner's tummy-wrapping girdle is very visibly showing through his costume.
Continuity mistake: After Garth attempts to convince Mr Scott that he is Captain Kirk and to beam him up, while he is banging his fists on the floor in anger he transforms back into himself and the fly like ring on his finger breaks and slides out of shot. It's quite hard to see but it does. The next time we see Garth's hand his ring is intact yet he has not transformed himself again to repair it.
Factual error: The Enterprise accidentally travels a short distance outside the galaxy and can't find its way back. But they'd have to travel for months to get so far outside the Milky Way that they couldn't, well, just turn around in the void and see it. Our galaxy is huge. 100,000 light years across. Very huge. And that barrier may surround the galaxy, but even it is big, pink and visible.
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Revealing mistake: During the court martial scene, a directorial error led to Kirk's exit from the briefing room in the wrong direction. He walks off screen into what would have been a solid wall or corner. The briefing room's only door is on the other side of the room.
Continuity mistake: During McCoy's struggle with the orderly, only half of the plastic colored bottles strewn on the table are knocked off onto the floor. But when Nurse Chapel hurries over to tranquilize the orderly, the rest of the bottles vanish, leaving the table completely clear.
Factual error: When Kirk is given the medicine badge, it's a stretchy elastic/Spandex headband. This is supposedly a completely pre-industrial culture paralleling the early Native American tribes. They have no fabric, no yarn, no spinning wheels - only hides and animal hair, neither of which can stretch a la Spandex.
Continuity mistake: Kirk calls Scott to beam up, and lowers the communicator from his face as he looks at McCoy. In the next shot, he's holding it to his mouth once more. The shot changes one more time, and it's lowered again.
Revealing mistake: Zarabeth tells Spock that Zor Khan only left her what was necessary to survive in the ice age. Mascara, eyeliner, lipstick and hairspray were apparently considered survival necessities. Yes, we know the actress "had" to wear make-up. But in a prehistoric setting, it shouldn't look as though she did. She could and should have been given a more "natural" make-up job - and an unlacquered hairdo.
Other mistake: At the end, Kirk teases Spock twice specifically about letting himself be hit on the head in order to determine which Kirk was genuine. But the phony Kirk never hit Spock on the head. He merely pushed Spock over and attacked the real Kirk. Clearly, the action sequence wound up differing from the scripted dialogue, and no one noticed. (Also clearly, Kirk is not speaking metaphorically here.)
00:45:30 - 00:49:20Jean G
Revealing mistake: Stock footage strikes again when Kirk orders the red alert. A shot of the bridge and view screen, with Kirk standing in front of his chair, once more switches Kirk out for a stand in, and Chekhov has gone and is replaced by what looks like from behind like a young woman or a man with a long neck. Also the central display between navigator and helm is now different from that earlier.
Continuity mistake: After partially healing him, Gem falls away from McCoy and lands, unconscious, perpendicular to the dais he's lying on. When Kirk and Spock rush over, however, she's suddenly moved several feet away and is now lying parallel to the dais.
00:44:50 - 00:45:35Jean G
Revealing mistake: For the final time in "Star Trek's" 3-season run, Chekov mysteriously vanishes from the bridge to be replaced by that tall blond doppelganger, thanks to an old piece of 1st season stock footage used for the special effects insertion of the view screen. The costumes are also noticeably different from 3rd season's uniforms.
Continuity mistake: Natira orders the landing party to kneel before the oracle. Spock does so about a foot-and-a-half to McCoy's left. As the shots change, Spock "jumps" to McCoy's immediate side, then back to his original position, etc.
Continuity mistake: When Kirk splits up the landing party, he asks McCoy to further inspect the vegetation. In the two shot, McCoy isn't wearing his tricorder, but in close-up, it's there, strapped over his left shoulder. Cut back to the two shot, though, and it's gone again.
Continuity mistake: As Mira is speaking with the alien's voice, Spock is behind a console that has a piece of equipment attached to it. From behind Spock, the piece is to his left, but the close ups of Spock show him close to and directly in front of it.
Other mistake: When Chapel comes into Sickbay and looks at the "dead" Captain, the camera goes to close up of Kirk, and he wakes up. After she yells for McCoy, the camera goes back to Kirk, and he goes back to sleep. The motions of him waking are obviously played in a slow reverse instead of him quickly closing his eyes.
Continuity mistake: When Mr. Scott asks Watkins to check the bypass valve, Watkins is facing the engineering boards with both hands on the panel. When we cut to a different angle, however, he's suddenly jumped to a position facing Scott with only one hand on the panel.
Continuity mistake: In Kirk's log entry, which he somehow makes from jail without a tricorder, he states that 5 witnesses heard him speak to the "spirits." This isn't true, and Kirk ought to know it. The crowd rushed in through an archway after he spoke to Spock and McCoy, and they were all too far away before to hear him.
00:10:50 - 00:26:00Jean G
Continuity mistake: When Losira comes for Kirk, he's holding Sulu's tricorder with both hands. When the angle changes to include her, he has it in one hand with his right hand at his side. Cut back to a three shot of Sulu, Kirk and McCoy, and Kirk has the tricorder in both hands again.
Audio problem: During the scene where Kirk is talking in the briefing room, the director was obviously not pleased with how James Doohan said his lines.Due to budget constraints, instead of re shooting the scene, they simply replaced Mr Scotts dialogue with another one.You can see it since at one point his lips are completely out of sync, even on the remastered edition.
Plot hole: The law officer who arrests Kirk recalls hearing Kirk call the "spirit" Bones. But he wasn't there when Kirk spoke to McCoy. He rushed into the scene several minutes later. If he's lying, how would he know that Kirk used the name Bones? He wasn't there to hear it. Even if he had been, Kirk did not refer to McCoy as Bones in that conversation.
00:10:50 - 00:19:50Jean G
Other mistake: In the final scene, Kirk is still in the transporter room, but does not have on a visor when the ambassador transports out. Spock has his visor on, but then you see Kirk walk out of the transporter room without a visor and he is not going mad.
Continuity mistake: In the 40th Anniversary release of the complete original series, this episode opens with Scotty at the conn, making an extended log entry, wearing his third-season swept-back hairstyle, and it is very obvious that he is visually mouthing several completely different sentences than we hear in the audio. After the opening credits roll, we next see Scotty wearing his more typical relaxed hairstyle with slight bangs. It is apparent that, in remastering and editing this episode, they inserted footage of Scotty from another episode altogether. For whatever reason, it is a glaring mistake of both continuity and audio editing.
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Continuity mistake: Just before Parmen starts mind-controlling Kirk, McCoy and Spock, he presents them with three gifts. Kirk receives a large, gold Greek shield, which the captain holds with both hands, in front of him, as the lengthy scene continues. In the wide shot, Kirk is holding the shield high up on his chest, completely obscuring his Federation insignia. In subsequent close-ups, Kirk is holding the shield down low, around waist-level, fully exposing his chest and insignia. Every time the camera cuts back to wide-shot, Kirk is again holding the shield up high on his chest.
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Plot hole: In the conference room, Spock informs Kirk that his theory of a Romulan cloaking device kept the sensors from detecting the ships. However, in S1:E14, "Balance of Terror", they figured out the cloaking device, and how it worked. Unless he was feeding into the deception, Spock shouldn't have had any theory when it was a fact.
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Plot hole: When the Medusan Ambassador Kollos and Dr. Jones materialize, the latter is wearing a protective visor and Mr. Spock can see that. Spock then mistakenly addresses Dr. Jones as Ambassador Kollos. Spock's suddenly illogical mistake seems odd: why should the Ambassador need to wear a visor? Shortly after, why do both Jones and Spock wear visors while carrying the Ambassador's still closed gasket to his cabin?
Other mistake: When preparing to go around again, Sulu and Checkov start working their controls. When there is a close up of Sulu's hand, it's obviously a re-used shot of Kirk's hand starting the 30 second count down timer on the Constellation in "The Doomsday Machine" (S2 E6).
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Other mistake: After the shot of McCoy checking Sickbay, there's a shot of Chekov. It was a quick shot but it can be seen that the film was run back and forth through about a second, as his movements can be seen to repeat rapidly in reverse and forward twice.
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Continuity mistake: When Kirk, Bones, Chekov, and Spock go over to the Defiant, the suits they have on have a black support bar in the left side of the headpiece. When the camera looks down at the dead men and back to Kirk, you see the bar is on the right, and his hair is parted on the right. The very next look at Kirk, the bar and the part of his hair is back on the left.
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Factual error: In the opening sequence, Spock identifies the alien ship as possessing "ion propulsion" which he says is "unique technology." Scotty is similarly impressed and says, "They could teach us a thing or two!" Kirk later comments that "Advanced ion propulsion is beyond even our capabilities." However, even back in the 1960s, ion propulsion was physically feasible, while Warp propulsion was complete fantasy. Ion propulsion of any kind could never even reach lightspeed and would be incredibly primitive compared to Warp technology. In fact, we in the 21st Century have already developed ion propulsion, but it will probably take many hundreds or thousands of years to develop anything even close to Warp technology.
Add timeCharles Austin Miller
Revealing mistake: Chekov covers Mara's mouth with his hand when he assaults her in the corridor. Kirk intervenes and throws Chekov against the opposite wall. Brown streaks form where Chekov's hands hit the wall, most likely from the brown makeup used to create Mara's skin tone.