The Doomsday Machine
The Enterprise discovers an ancient and humongous world-killing engine that has the potential to cause untold destruction if utilized. Seeing as this episode hails from the height of the Cold War in the 1960s, it’s not hard to see it as something of an allegory for the paranoia the US was suffering during this time while under the threat of nuclear warfare.
More than that, though, “The Doomsday Machine” works on a dramatic level as well as a thematic one as there’s a great one-off character in the form of Commodore Matt Decker, the only survivor of a previous Starfleet ship to investigate the machine who’s suffering from PTSD and has been left crazed, which leads to clashes with Kirk – technically the inferior officer in this case.
This is a smartly-written “sci-fi Moby Dick” tale which combines huge stakes with the small-scale story of a man driven to the end of his tether. Plus, it has one of the most iconic monsters from the original series.
Amok Time
Despite being known for his logical, emotionally-distant ways, Spock’s at his best when Leonard Nimoy is allowed to stretch the character a little and show the Vulcan’s half-human side. “Amok Time” is perhaps the best example of this in the series as the season 2 premiere gives us our first trip to Spock’s home planet. The visit is necessitated because Spock’s caught in the throes of pon farr, the Vulcan mating ritual that takes hold of the males of the species every seven years and practically drives them crazy.
When Spock returns home to his betrothed, the beguiling T’Pring, he’s forced to engage in combat with another mate of her choosing in order to win her affections – and his opponent is none other than Kirk. As well as giving us a fascinating glimpse into Vulcan society, this is also a great one for the Spock and Kirk friendship as their battle (which is as awesome as you’d expect) oddly brings them closer together.
And let’s not forget the touching moment shared between Spock and Bones, too, in which the Vulcan admits the good doctor is one of his closest friends.