Question: What caused Captain Garth to go mad?
For the World is Hollow and I Have Touched the Sky - S3-E8
Question: Dr. McCoy stays on the planet Yonada as one of Yonada's people, but doesn't change his Starfleet uniform to what the people of Yonada are wearing. Why not? He chose to stay and no longer wanted to be on the Enterprise.
Answer: There's no explanation. He may not have completely adjusted to living there or gotten around to getting new clothing. He was also still a member of Star Fleet and would wear his uniform until he formally resigned. TV shows back then were cheaply made and rather lax about details like that. They may simply have deemed it unnecessary to change McCoy's costume. It could also be interpreted as foreshadowing that he would return to Star Fleet. Also, in all the Star Trek series, miscellaneous characters would often wear only one outfit, even though the story may take place over many days. In the early days of TNG, Counselor Troi wore the same outfit in nearly every episode until she started wearing a uniform later in the series. The practical logistical reason for a character wearing one costume is that it maintains continuity for the post-production editing process.
Question: As Captain Kirk didn't die until the film 'Star Trek: Generations' (1994), what happened in the last episode of the series?
Answer: The original series didn't have an ending, it was just cancelled. The last episode was "Turnabout Intruder" where Kirk and Dr. Janet Lester switch bodies and then switch back.
For the World is Hollow and I Have Touched the Sky - S3-E8
Question: How did Dr McCoy know that Kirk and Spock were going to beam down? Kirk didn't call him to beam down with them.
Answer: Their mission is to explore strange new worlds, seek out new life and civilizations. He knew they wouldn't just fly away. Besides any expedition would require a leader, a scientist and a medical doctor.
Question: If McCoy was so worried about Kirk, why he didn't stay on the planet to continue the search?
Answer: McCoy's place is aboard the Enterprise. If they fail to deflect the asteroid, everyone left on the planet, including McCoy if he remains behind, will be killed. If they are successful, then both Spock and McCoy can return to continue searching for Kirk. McCoy, being a Star Fleet officer and a doctor, knows that his first duty is to the Enterprise and its crew. "The needs of the many outweighs the needs of the few, or the one," certainly applies here, and it is what Kirk would have expected of him.
Question: How did Dr. McCoy know that the figure next to Kirk and Spock was Surak? The Enterprise was not watching when they were introduced.
Answer: Everyone knows who George Washington is, also Abraham Lincoln, Thomas Jefferson and countless others. When you join Starfleet, you have to know other planets, their people and their histories.
Question: Surak is a Vulcan with better hearing than humans and greater strength than humans. How was he able to be killed so easy?
Answer: Maybe not so easily, Klingons are known for their strength and fierce fighting styles, plus he went up against four of them.
Question: Spock says Kirk went to a time ahead of him and Dr. McCoy. How did he know that?
Answer: Spock understood how the machine worked, by sending a person to the time they were viewing. When the three were near the time portal, they could hear each other and those around them. Spock would have been able to hear the group of people who took Kirk and heard them talk about thievery, purse cutting, and the law, etc. He made a logical assumption Kirk is in a more advanced and "civilized" time period that would have to be much later than the ice age.
Answer: He was seriously injured during a rescue mission, the result of the accident and his injuries also left his mind unstable and he began a descent into madness. While not a lot of detail is given, you can compare it to war veterans who experience shell shock or PTSD.
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