Continuity mistake: When the Thasians restore Yeoman Rand on the bridge she's barefoot, but when Charlie begs Kirk not to let the Thasians take him because he can't live with them anymore, we see Rand wearing a white fluffy slipper (which she wasn't holding when she reappeared), then she's back to being barefoot again. (00:44:42)
Continuity mistake: When "good" Kirk beams up from the planet, the insignia on his shirt is not there. Then it appears when he's walking with Scotty. (00:03:00 - 00:05:25)
Continuity mistake: When Capt. Kirk and Charlie enter the turbolift heading for the bridge, Kirk is wearing one style of tunic and when the turbolift arrives on the bridge, Kirk is wearing a completely different tunic. (00:15:14)
Continuity mistake: All during the episode there are scratches on the left cheek of the "evil" Kirk. When the "Good" Kirk and the evil Kirk confront each other on the bridge, there's a shot where the scratches are on the right cheek of the evil Kirk.
Where No Man Has Gone Before - S1-E4
Continuity mistake: When Kirk exits the turbolift he sits in the captain's chair, and Yeoman Smith stands behind him with barely any space between them, but in the shot facing the main viewscreen Smith is gone, and in the next shot she reappears right behind Kirk again. Smith continues to disappear and reappear in following shots. (00:04:00)
Where No Man Has Gone Before - S1-E4
Continuity mistake: When Kirk is fighting Gary Mitchell, his tombstone reads James R. Kirk. Kirk's middle name is Tiberius. Mitchell is a friend of long standing and would not have got it wrong. (00:44:30)
Mudd's Women - S1-E7
Continuity mistake: As the women are beaming aboard in the transporter room, McCoy's uniform switches from the standard blue tunic to his short-sleeved medical smock and back again between shots. (00:05:55)
The Man Trap - S1-E2
Continuity mistake: When Rand brings Sulu the plate of food, it has a bowl of colored cubes on it. Then there's a cut to a close-up of Sulu eating the cubes when Green is staring at it, and the bowl is now a plate. Then in the long shot it's a bowl again. (00:24:22)
Continuity mistake: Initially, the Enterprise orbits Psi 2000 as the planet turns westward. But in later shots, on the bridge view screen, the planet has reversed directions and now turns eastward. (00:04:05 - 00:12:00)
What Are Little Girls Made Of? - S1-E8
Continuity mistake: When the android Kirk boards the Enterprise and takes a "command pack," he walks out and down to the transporter, but he doesn't have the pack in his hand.
Continuity mistake: When Kirk is facing the Horta he has his phaser in his right hand when seen from the front but when seen from behind he has his communicator in his left hand and no phaser. (00:31:00 - 00:38:00)
Tomorrow is Yesterday - S1-E20
Continuity mistake: When Kirk and Sulu enter the records room, they pick the lock. Later when they beam the officer back down, he enters the room without unlocking the door. The room should be locked since they beamed him down in the "past" erasing their having been on Earth and in the records room.
The Man Trap - S1-E2
Continuity mistake: When they first arrive on the planet, the tricorder Kirk is holding for McCoy starts on his left shoulder, disappears in the next shot, then in the next shot after that reappears in his right hand.
Continuity mistake: The ropes tying Yeoman Rand to the chair keep changing positions (above her elbows or below her elbows) between shots. (00:39:40)
What Are Little Girls Made Of? - S1-E8
Continuity mistake: While Kirk's trying to convince Ruk that Korby's creating the same danger just like the Old Ones, when Kirk tells him that humans are full of unpredictable emotions, the closeup of Kirk is a flipped shot (the jumpsuit's blue and green switch sides).
Mudd's Women - S1-E7
Continuity mistake: During Mudd's hearing Eve's sitting in the chair beside Mudd, but when Kirk states that the hearing is closed and that Mud will be handed over to legal authorities, in the wideshot Eve's chair is empty, but in the next closeup Eve is still sitting in the chair. (00:18:15)
The City on the Edge of Forever - S1-E29
Continuity mistake: When McCoy arrives in NYC while the man is stealing a bottle of milk, in the closeup the actor's ring finger is partially amputated, but when he steals McCoy's phaser his finger is intact in the closeup.
The Conscience of the King - S1-E14
Continuity mistake: After Kirk introduces himself to Lenore at Leighton's cocktail party, when she tells him, "Karidian is a most unusual man... That was my father," Lenore holds the goblet in her left hand as she takes a sip, but next shot the goblet is suddenly in her right hand as she sips.
A Taste of Armageddon - S1-E24
Continuity mistake: Just after the ship is first attacked, Scotty tells McCoy, "We can't fire full phasers with our screens up." Say what? The Enterprise couldn't operate transporters with the shields up, but it fired its phasers, full or otherwise, with the screens up every time it went into battle, and always had. If they'd been forced to shut their shields down every time they fired, the Enterprise would have been history long before this. (00:23:30)
Suggested correction: This wasn't a continuous shot though, we just don't know where they get the insignia, it could have been in his pocket. Both Kirk and Sulu are on the planet's surface without their insignia. And when "evil" Kirk beams up, he too doesn't have it on, even though later he does.
Bishop73
What possible reason could there be for the Enterprise Insignia, which is stitched to every uniform, to be in 'Evil' Kirk's pocket? No character has done this in any episode of Star Trek. They don't get them from anywhere, they are a part of their uniforms.