Star Trek (1966)

Spock's Brain - S3-E1

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.

Is There in Truth No Beauty? - S3-E5

Revealing mistake: The colorful nebulae of the energy barrier are showing through the hull of the suddenly-transparent Enterprise as it heads back into the galaxy. (00:37:40)

Is There in Truth No Beauty? - S3-E5

Revealing mistake: During the fight in engineering, Marvick's kick, throwing one of the engineering crewmen violently back against the wall, misses by an obvious mile. (00:20:10)

The Cloudminders - S3-E21

Continuity mistake: In "Amok Time" Spock described Vulcan mating rituals as "a thing no out-worlder may know" - here he goes on about them with Droxine at some length.

The Way to Eden - S3-E20

Revealing mistake: Due to close-ups that were cut in backwards, Kirk appears in reverse, with his uniform insignia on the wrong side, twice in this episode: once in the corridor outside sickbay, and again near the shuttle craft on Eden. (00:18:15 - 00:46:55)

Spock's Brain - S3-E1

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. (00:13:10)

Is There in Truth No Beauty? - S3-E5

Continuity mistake: At the dinner for Miranda, Kirk drains his glass. No one refills it, but it's nearly full again a few shots later. (00:08:25 - 00:10:35)

Let That Be Your Last Battlefield - S3-E15

Revealing mistake: Because stock special effects footage was used, the shuttle supposedly "stolen from Starbase 4 two weeks ago" is plainly marked "Galileo, NCC 1701/7, USS Enterprise." (00:02:15)

The Paradise Syndrome - S3-E3

Factual error: Mr. Spock states that the asteroid is almost as large as the Earth's Moon. Such big bodies must be predominantly spherical due to their own gravity. However, the asteroid is very elongated, with a very irregularly shaped surface. (00:06:40)

The Savage Curtain - S3-E22

Deliberate mistake: So that he can look in the right direction, toward Lincoln, a shot of Kirk is reversed before the first battle, putting his uniform insignia on the wrong side. (00:25:45)

Is There in Truth No Beauty? - S3-E5

Visible crew/equipment: When Kirk turns to follow Miranda across the arboretum, the camera shadow is briefly visible on the wall at the lower left of the screen. (00:29:50)

Spectre of the Gun - S3-E6

Continuity mistake: When Chekov sits outside the general store chatting with Sylvia, his left arm and her right alternate from entwined to un-entwined and back again as the shots change. (00:27:40)

The Tholian Web - S3-E9

Visible crew/equipment: A camera shadow briefly intrudes on the right side of the screen as Kirk asks Mr. Scott about the sensor readings. (00:00:55)

Turnabout Intruder - S3-E24

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. (00:39:15)

The Way to Eden - S3-E20

Revealing mistake: On the surface of Eden, Spock finds Adam dead under a fruit tree. But the corpse's fingers are still moving. (00:45:20)

The Empath - S3-E12

Continuity mistake: During Kirk's torture scenes, the back shots have Kirk's arms stretched wide apart and yanked straight - the front shots have the chains going overhead and his arms are bent at the elbows.

Whom Gods Destroy - S3-E14

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.

All Our Yesterdays - S3-E23

Continuity mistake: When the prosecutor visits the cell, Kirk's hands on the bars change positions when the camera angle reverses. From the inside, there's one bar between Kirk's hands. From outside, there are two. (00:28:10)

The Lights of Zetar - S3-E18

Other mistake: Scotty has a science patch on instead of the engineering patch in this episode.

The Way to Eden - S3-E20

Revealing mistake: A re-used sickbay scene taken from an earlier episode causes Nurse Chapel to instantly revert to her old hairdo as the sound waves make her fall unconscious. (00:41:00)