Say you want a Spock episode? I say that episode finally arrive, halfway through the season!
Sure, "The Menagerie" two-parter featured everyone's favorite Vulcan, but more or less by default. Even "Balance of Terror" put considerable focus on him. But these were incidental. "The Galileo Seven" is the first time he's truly on his own, having to defend himself with no more help than Dr. McCoy. Who can hardly be considered Spock's most objective observer.
The rest of the away team, stranded on an alien planet after an away mission gone awry, looks to Spock to either save or finally reveal his true colors and fail to live up to his lofty ideals. Be the devil NBC executives considered him in the original pilot, "The Cage," when they announced he was the one element they found most objectionable. Yet not only did Spock survive while everything else around him changed, he became the true breakout character of the series.
Eventually, arguably and quite definitively eclipsing even his good friend Kirk, in fact. Go ahead. Just try to imagine the franchise without Spock. It's impossible. No one would remember it. It certainly wouldn't have gotten so many movies, additional series, a whole new incarnation.
So this is the first time the series really gets to acknowledge that. It's a defense of the character, really. And a darn good one, a spectacular one. A story so good it would be echoed many times over (Voyager's resident Vulcan, Tuvok, had at least two such episodes, "Innocence" and "Rise!").
When the chips are down, Spock delivers. He's easily good enough to be the captain. Yet he constantly faces the bigotry of his crewmates. In Gene Roddenberry's perfect future, humanity has finally found peace with itself. But not exactly with other species. Spock is the embodiment of that, and this is the episode you need to see to fully understand that.
For a series that very rarely put a direct focus on any character besides Kirk, "Galileo Seven" is a powerful reminder, too, that Spock could easily hold his own. Logical.
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