Shore Leave - S1-E16
Continuity mistake: Don Juan tears Yeoman Barrows' tunic at the right shoulder. Near the end, when she changes from the fairy tale dress back into the tunic, the torn right shoulder is suddenly mended. They're cut off from the ship by the power drain, so she couldn't have beamed up for a new one. She emerges from the bushes after changing, and now her tunic is torn at the left shoulder. (00:43:25)
Operation -- Annihilate! - S1-E30
Continuity mistake: When they put the satellites in orbit, Sulu announces they are in place. Then Kirk says "Energize" and the next shot shows the helmsman station and Sulu is absent - some guy in a red shirt is there instead. (00:45:30)
Continuity mistake: After Spock mind melds with Nomad, Kirk hustles him out into the corridor. In the shots taken from behind Kirk, the Captain's left hand is high on Spock's shoulder. In the reverse angles, his hand is several inches lower on Spock's arm. (00:35:00)
Character mistake: When Spock and Kirk pursue the Horta, they come to a fork in the tunnel. Kirk points right and tells Spock to go left. Then he points left and says he'll go right.
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. (00:14:40)
Continuity mistake: After his initial mind meld with the horta, Spock tells Kirk, "That's all I got, Captain: waves and waves of searing pain." A minute later, he says that it's "a highly intelligent, extremely sophisticated animal" that calls itself a horta. Apparently, waves of searing pain were not all that he got after all. Unlike Spock to be so imprecise.
Continuity mistake: The shards of the goblet Spock breaks change quantity and position on the table with the fruit bowl on it. (00:28:30 - 00:31:30)
Continuity mistake: When Isis meows and enters the inner office, the door is open several inches and the lights inside the room are on. When Gary Seven follows her in a few moments later, the door has nearly closed itself and the lights inside are off. (00:20:25)
Continuity mistake: In the briefing room, Hengist and the Prefect are sitting in chairs against the wall at least a foot apart, with bright overhead lighting that casts no shadows on the wall behind them. When we cut to a two-shot of them, however, they're suddenly shoulder-to-shoulder with almost no space between them, and the lighting changes to cast very dark shadows behind them. (00:28:20)
Continuity mistake: The shiny gold blanket covering the dying Commissioner Hedford is tucked up to her neck in close-ups, but only reaches her upper waist in full shots. (00:36:45)
Space Seed - S1-E23
Continuity mistake: When the landing party beams over at the beginning, the transporting officer is wearing a blue jumpsuit, but when they go to the closeup of his hands, they have a red uniform, two braid stripes, and are the standard shot they use when Scotty does the transporting. (00:05:05)
Continuity mistake: In one scene the Enterprise's phasers were pink instead of blue.
Continuity mistake: When Scotty gets drunk and tosses an empty bottle away, there's a dubbed in sound of glass breaking, but when he collapses, the bottle is unbroken at his feet.
Continuity mistake: During the coup attempt, one Capellan fights with the leader and gets stabbed. Before and after he is stabbed, the man's outfit changes entirely (look at the fur scarf, which goes from purple to orange.) His costume also changes color.
Revealing mistake: McCoy's stunt double's face is visible several times during the fight with the berserk orderly in the sickbay lab. (00:19:15)
The Return of the Archons - S1-E22
Continuity mistake: In the exterior shot, the double front doors of Reger's house have large curtained windows in them. After the Enterprise landing party rushes inside and closes the doors, however, they're suddenly solid wood with no windows. (00:06:35)
The Corbomite Maneuver - S1-E11
Continuity mistake: As Balok's 10 minutes are counting down, McCoy comes onto the bridge wearing a standard blue velour uniform. A few minutes later, when Spock says he can bring up Balok's image, McCoy is suddenly wearing his medical tunic with the different fabric and collar. Then when Bailey starts losing it, McCoy is back in the regular velour costume again.
Revealing mistake: After Kirk and the crew arrive underground, he stuns Kira and removes her bracelet. After he removes it, the unconcious woman quite deliberately lays her hand flat on the ground. (00:21:15)
Character mistake: Spock tells Zarabeth he came from a world "millions of light-years away." The galaxy is only about 100,000 light-years across - the area the Federation has explored even smaller.
Continuity mistake: Dr. McCoy's medical tunic has an engineering patch on it, instead of the science patch it should have.
Answer: Kirk was getting his physical and Dr. McCoy probably turned off communications, because if he hadn't, Kirk would have left and headed straight for the bridge, leaving McCoy irritated.