All Our Yesterdays
The people of a dying world escape to their past, with the help of librarian Mr. Atoz. He mistakes Kirk, Spock, and McCoy for inhabitants, and thrusts them into climates where survival is uncertain.
Yay, a good episode! One to stand alongside the better installments of the first two seasons. The time travel concept is cast in a new light, the atavachron is an intriguing and useful device, and what's this? Small silver discs used to store information? Fascinating. But best of all is the interaction between Spock and McCoy, and of course Zarabeth. The "reverting to my ancestors" doesn't quite jive, but it was Nimoy's quick alternative to zero explanation. We're eternally thankful for that. McCoy will probably reconsider going on his "green-blood-so-and-so" rants anytime soon, but they're actually important this time. The doc's "Are you trying to kill me, Spock?" is delivered perfectly and brings the Vulcan to his wits. Jim, meanwhile, is stuck in a bad costume drama and proves resourceful as ever. Nice touch that this society thinks technology is magic. (Arthur C. Clarke would approve.) The captain's wrestling with Atoz is amusing. But this is a rather dark episode, and might have made a more appropriate series finale than the bizarre Turnabout Intruder.
Spock Saves the Day: The - er - cold puts the first officer out of commission.
Oops: It's hard to hold Spock accountable for his behavior when in altered states. Sufficed to say he is entirely self-serving till McCoy shakes him into realizing his neglected duties. Also, he eats meat.
Developments: We've seen Spock in a state of bliss thanks to the spores, break down in The Naked Time, and reduced to his base instincts when in pon farr. Yet this is the first time we see Spock utterly stripped of his rigid emotional discipline, and still on top of his game. He is one scary dude. He also might be considered the equivalent of Kirk's "imposter" in The Enemy Within. Some would argue that he's also lost the capacity for rational thought, but he finds logical reasons for staying in the cave.
While can still think, his passions overrun him. Ultimately, however, his loyalty to Kirk and his ship proves stronger than his newfound love for Zarabeth. To his credit, he makes attempts to regain control throughout, noticing he's slipping. His companions try to sway him to either side. But only McCoy's insight as to why he is "not himself" allows him to regain composure. In the end all is forgiven, but not likely forgotten, by McCoy or viewers.