7. Space Seed
Space Seed was not only one of the original series best episodes, but it spawned the plot for the 1982 motion picture Star Trek II: The Wrath of Khan, considered by many to be the best of the original crews big screen outings. One of the most memorable Trek villains, Khan Noonien Singh, appears in this first season episode and played with a fierce, understated menace by Ricardo Montalban. When the Enterprise encounters a spaceship adrift in space, they discover hibernating humans within. These humans aren't just lost in spacetheyve been marooned there for centuries for their crimes against the people of Earth. And of course, like many TOS villains, they take over the Enterprise. Space Seed proffers several classical dramatic themes, including the quest for power and how power can be a seductive force. The episode dealt with the genetic alteration of human beings, a common sci-fi element today, but in the 1960s such a practice was a reference to the atrocities committed by the Third Reich in its quest to purify the Aryan race. The back story to Space Seed mentions the eugenics wars of the 1990s, during which Khan and his army, genetically engineered as superior human beings, attempt to take over the world.
Memorable Line: "I signed aboard this ship to practice medicine, not to have my atoms scattered back and forth across space by this gadget." - McCoy