Episode 3-20, Tin Man

Tin Man is a wonderful episode, the sort of great science fiction story that Trek does best. Ancient aliens that are living spaceships, telepathic communication, androids understanding human emotion, space battles with a powerful foe, it is all here. The casting is also excellent with Harry Groener as the troubled empath. Casting can make or break an episode and they nail this one. This is one of my favorites.