The Squire of Gothos
Kirk and the away team find themselves at the mercy of Trelane, a being with the power to rearrange matter to suit his own whims, and who sees the Enterprise officers as play things.
One of the more intriguing ways I've heard Kirk, Spock, and McCoy's relationship summarized is as child, father, and mother. It certainly works in this episode. Kirk seems to not-so-secretly enjoy his play dates with cosmic fop Trelane, while Spock, the disapproving dad, attempts to break it up. (McCoy stands back and nags as usual.) The planet chasing the ship is actually the most inventive scene. Meanwhile, Trelane's drawing rooms offer a glimpse of the past-Earth settings common in Season Two. While the dances, dinners, and duels all shout "fill to time," the trial scene has some weight. It would have been satisfying if Kirk had actually outwitted his opponent. Nay, super beings similar to those in Charlie X spoil his fun, and our captain must return to teasing Spock about his possible childhood exploits. Even in the far reaches of the galaxy, family life carries on.
Spock Saves the Day: Spock beams the missing officers back to the ship and helps destroy Trelane's mirror.
Oops: Poor Spock. When Jim teases you about something about which you know absolutely nothing, just nod.
Developments: As mentioned, Spock is father figure here. He has no time for games, always cutting to the point or cutting off Trelane. He may be right in wanting to end this silliness ASAP.