The Return of the Archons - S1-E22
Continuity mistake: As Marpon talks to Spock, his right hand goes from being palm forward toward Spock, to being vertical, palm open, thumb upwards, and back.
The Return of the Archons - S1-E22
Revealing mistake: In the holding cell, as Spock attempts to analyze McCoy's mental state, the alcove is brightly lit a hand held lamp. As the camera pulls back, the light is seen to move, and then is turned off.
The Return of the Archons - S1-E22
Continuity mistake: As Kirk talks to an "absorbed" McCoy, in the back-and-forth cuts between them, the part in Kirk's hair jumps from left to right and back.
The Return of the Archons - S1-E22
Continuity mistake: After the Law Giver kills Tamar, he starts to raise his staff. When the camera is in a close up on the Law Giver a second later, it's straight out again. (00:13:15)
Revealing mistake: As Kirk turns to run on the castle steps, an iron bar barricade appears, blocking his path. When it does, watch the castle wall, and the barricade. It seems to slide just a few inches to line up correctly in the shot, showing poor editing.
Continuity mistake: After swiping at Trelane to score a hit, which Trelane avoids easily, Kirk throws the sword away, which hits a bush as it falls. When Trelane calls up another sword, the bush suddenly stops moving.
The Corbomite Maneuver - S1-E11
Continuity mistake: While beaming to the alien ship, McCoy has his hands on his knees. When materializing, they are beside his thighs.
The Corbomite Maneuver - S1-E11
Revealing mistake: In Kirk's quarters, as he touches the desk top comm panel, it noticeably slides a little rather than being fixed in place.
Mudd's Women - S1-E7
Visible crew/equipment: In the briefing room, as the camera moves to its left along the seated figures, the camera rig is reflected in the glass of the communication view screen.
Mudd's Women - S1-E7
Continuity mistake: In the briefing room, after Mudd is forced to give his real name, the screen lights up with his record of offenses. In the picture, his image has the ear bauble on the right ear, but he wears it on the left.
Where No Man Has Gone Before - S1-E4
Revealing mistake: The readers in Sick Bay are supposed to be display screens, a type of CRT, for reading material. Mitchell turns his off to rest, but the words are still plainly visible.
Where No Man Has Gone Before - S1-E4
Visible crew/equipment: As the camera is close up on Kirk, and as he addresses the ship, the shadow of the boom mike plays on Smith's neck. (00:04:35)
Where No Man Has Gone Before - S1-E4
Continuity mistake: As Kirk, Spock and Mitchell exit the lift, Yeoman Smith is by the door and begins to follow, and an un-named guy walks by her and into the lift. In the wide shot of the bridge, the actions of Smith and the crewman are repeated.
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.