The Tholian Web
While exploring a ship slipping in and out of their dimension, Kirk is pulled in. Spock and McCoy must find him, and cures for the effects of thin space and each other.
Again with the slight plot, but here the characters actions are well conceived and sensible, and the aliens intriguing. The "other dimension" business isn't explained in the context of what's come before (in The Alternative Factor and more importantly, Mirror, Mirror) but isn't jarring. It's simply an excuse for Kirk to disappear and for the remaining officers' increased irritation with one another. Spock and McCoy's scenes are perfect: we learn more about them in this one hour than all third season episodes to this point. It's made clear that only together can they be Kirk. It's a little off-putting that McCoy doubts Uhura so quickly, "unstable woman" that she is. If it had been a male officer, he'd believe, and does. I must mention here that Kirk is wearing the worst space suit ever. For a series set almost entirely in space, they never have designed a decent looking space suit. And who would have thought space madness could be cured with orange Tang? Mixed with Scotch, no less.
Spock Saves the Day: Spock takes command, tries to negotiate with the Tholians, keeps the frenzied crew under control, and rescues his captain.
Oops: Little too harsh with Bones. He's only trying to help.
Developments: Spock's style of command hasn't much changed since The Galileo Seven, right down to the half-hearted funeral service: this time for his closest friend. The Vulcan's mind is quite focused on the ship's problems; he doesn't seem to grapple with or even accept that Kirk is dead. He is at last able to make peace with McCoy, and one has the sense they could carry on without their captain. But fortunately, that's not a concern.