In the first visit to Gene Roddenberry's "god box" since some of the earliest episodes of the series ("Where No Man Has Gone Before," "Charlie X"), Kirk matches wits with a being of considerable power, whom later fans equated with Next Generation's Q.
Although similar to the earlier and later "god box" episodes, "Squire of Gothos" is probably more comparable to "Shore Leave" in that Trelane's activities are a lot more fanciful than outright menacing, except for the character's vast abilities. Just as famous as the character himself is what he's ultimately revealed to be, a l'enfant terrible, a child who at the end of the episode is reprimanded by his parents. A true twist ending!
The parallels with the later Q character are so obvious that Peter David incorporated the connection into his novel Q Squared. Another quasi-sequel was actually the semi-complete original cast reunion in the Futurama episode "Where No Fan Has Gone Before," which borrows the twist ending.
Probably an episode best kept to fans of the series, although its importance should be stressed. Even if it were mere coincidence, there's much more of Trelane in Q than all the androids of the series combined in relation to Data. Still, it easily stands out from the pack and comfortably distances itself from similar episodes. Roddenberry's obsession with god-like beings is certainly apparent enough. Once in a while he just had fun with it. And thank goodness!
franchise * series * essential * character