Kirk learns his final lesson when he switches bodies with a woman who gets him pregnant.
Well, most of them anyway. Quite a few got used up in previous time-travel episodes. (Or were those tomorrows?) Spock falls in love with a dead woman.
Kirk kicks Genghis Khan’s ass. (“KHAAAAAAN!!!”) This teaches a more highly advanced civilization the meaning of good, bad, and ugly.
Kirk solves prejudice with gas masks.
Kirk learns that flower children are really OK, just misguided.
Kirk punches out a 4,000-year-old man, falls in love with his daughter, and talks another robot to death.
The Enterprise gets attacked by another bunch of flashing lights, which wreaks havoc with traffic but saves oodles on the special effects budget.
Kirk discovers a planet populated completely by his illegitimate children. He solves their overpopulation problem by teaching them the true meaning of VD.
Killer holograms survive, unfortunately, but at least they’re pretty.
The Enterprise encounters two strange beings who are at war with each other because they are each other’s mirror image, which leads to complications when they try to shave.