Continuity mistake: The indicators radically change positions when Spock gets on the bio bed.
Continuity mistake: When Sulu confronts the men in the corridor, his epee goes from perfectly straight to having a slight crook, then back to straight when he appears on the bridge.
Continuity mistake: As Joe draws back and stands up, he pulls a knife. First, it's sharp side up, then it's suddenly blade down.
The Corbomite Maneuver - S1-E11
Continuity mistake: As McCoy first appears from the elevator behind Kirk, then follows him in, his hairline changes from a widow's peak to straight across.
The Corbomite Maneuver - S1-E11
Continuity mistake: When the cube first meets the Enterprise, it's spinning clockwise on its axis. Later, it's spinning counter-clockwise.
This Side of Paradise - S1-E25
Continuity mistake: As Kirk sits on the deserted bridge, there is nothing out of the ordinary with him. After he sits at the helm position, the camera looks at him over the console, and there's suddenly a spore spewing plant to shoot him.
Suggested correction: The plant did not suddenly appear, it was there from earlier in the episode.
This Side of Paradise - S1-E25
Other mistake: After Spock is hit with the spores, he goes down on all fours in pain. As he writhes around, the skin tone of his ears is vastly different to his other makeup.
A Taste of Armageddon - S1-E24
Continuity mistake: The chamber the guards try to shove Fox in is open when Spock shoos everyone away. But it's closed when he goes to blast it.
A Taste of Armageddon - S1-E24
Continuity mistake: At the door, as Spock gives Yeoman Tamura her orders, his hands are in front of him. In the close up, they are suddenly by his sides.
The Return of the Archons - S1-E22
Other mistake: On the bridge, as the camera looks at the view screen, there is a flashing blue light reflecting on the console in front of Sulu, but there is no light other than scanner under the viewer flashing and it's too far away to project light that far, and it's amber colored.
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.