Plot hole: Spock presents himself to Dr. McCoy in sickbay to be relieved of duty for "killing" Captain Kirk. (It's done, of course, so Kirk can walk out of the room and surprise Spock by being alive) But Bones has no command authority since this is a legal/military matter. If Spock believes he should be relieved for breaking regulations and committing murder, and thus confined until court-martial, Scotty would be the one to do it, as he is the next senior officer. And this is not a character mistake, Spock quotes regulations regularly, there is no way he'd ignore chain of command.

Continuity: When Spock and Captain Kirk are fighting with the spears, watch Kirk closely after he has been slashed by Spock and his shirt ripped. Both the ripped shirt and scar appear and disappear throughout the rest of the fight.

Revealing: In the middle of the episode Spock goes to Plack Tao to meditate. We see a shot of him and then we see some other people. At this moment look directly behind all of them and you will see Spock waiting for his next shot.

Continuity: Just before T'Pring calls for the challenge, there's a wide shot of her going toward the gong. Then they cut to a closeup and she is standing beside Stonn, and then she starts moving toward the gong again.

Continuity: Kyle reports the landing party's whereabouts on the surface, and Spock asks, "And Apollo?" Kirk had no chance to call the ship after Apollo revealed his name - so Spock should not have known it.

Factual error: Spock says they've only managed to punch holes in the force field large enough to fire through. But when the Enterprise fires, the force field (in the shape of Apollo's hand) is no longer there at all.

Continuity: The fruit bowl disappears from the table altogether just before the Enterprise fires on the temple. The small statue that's been there from the start vanishes as well.

Revealing: When Apollo first grows large, the shimmering edge of the special effects matte is visible in the sky just above his right shoulder.

Continuity: Apollo's lightning bolt throws Scotty across the table and dislodges a big bunch of green grapes from the fruit bowl. They fall onto the table. But when Kirk's crew later assemble at the table, the green grapes aren't there, or in the bowl, or anywhere in the temple. They magically reappear in the bowl just after Spock gets through to Kirk on the communicator.

Continuity: 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.

Continuity: When Nomad initially attacks the Enterprise, Uhura appears/disappears in subsequent shots of the bridge.

Revealing: When Nomad's bolt sends Scotty flying across the bridge, you can see the two rubber mats placed on the floor for the stunt man to land on.

Revealing: When the Enterprise is attacked in the prologue, some of the crew grab onto the central console (that Sulu and Chekov usually sit at). The console noticeably lifts up from the stage surface, almost falling over. Twice.

Continuity: When Kirk sits down to consult the computer, the big green potted plant on the shelf behind him is there in full shots and missing in close-ups. It's much too large to be completely hidden behind him: if it shows up behind his head in full shot, it should show in close-ups, too, but it doesn't. It's not there.

Continuity: Kirk punches the Imperial crewman that helps him in the face, but when the guy falls on the ground he's holding his side.

Continuity: A subtle mistake, but when Spock is lying on the table in sick bay and recovers, the readings on the monitor are in the normal range. However Spock, as a Vulcan, produces very unusual readings on the monitors in other episodes.

Revealing: During the fist fight between the transported crew and Spock, the use of stunt doubles in the wide shot is quite obvious.

Revealing: Kirk orders Marple to cut around a rock to the right and make a noise to distract their observer. But the actor appears to slightly screw up his cue: Marple promptly traverses the rock to the left instead of the right.

Continuity: When the giant cat breaks down the cell door, Korob falls beneath it face down with his head toward the door. In the very next shot, he's in a completely different position - face up with his feet toward the door.

Continuity: After Korob fails to get information, he tells Scott and Sulu to take them out. They escort Spock and Kirk over to the door past McCoy, but don't stop (apparently DeForrest missed his cue.)