The Immunity Syndrome
A "zone of darkness" slowly pulls the Enterprise towards its center, inhabited by a giant ameoba. With one cell causing such destruction, it must be stopped before it divides and multiples.
Probably one of the better "big scary thing in space" episodes, though there's an air of routine for officers and viewers alike. The ameoba looks more like a psychodelic paisley than a single-celled animal, but the science is pretty solid. Hey, if it redefines Kirk's concept of scale ("We'd be the virus!") it's worth encountering. The show's first half is very slow, with the bridge crew having nothing to report to their fatieged and irritable captain. (Yup, getting those gangsters in line was exhausting ...) Spock recieves his most useful info through telepathic link, a good touch. His rivalry with Bones provides the plot's crux . Kirk is caught in center; who to send to his death? The one less likely to die, of course! Fortunately Spock just has to fall over a few times. McCoy could've survived that. " Shut up, Spock, we're rescuing you!" is an appropriate reply to snarky Spock. It's nice for once to be McCoy considered for his scientific knowledge, specifically biology. We have to wonder what on Earth he's thinking when elsewhere he says "I'm no scientist." And after all this Kirk's scientific solution is another antimatter bomb. It blew up good.
Spock Saves the Day: Spock senses the "death" of the Intrepid and warns of danger, then gathers information on the ameoba from the shuttle.
Oops: Tell Kirk anything, because he won't accept nothing.
Developments: Spock's telepathic abilities continue to be explored. He can sense the death of 400 Vulcans and their ship light years away, causing a moment of pain. Bones admits it's possible, the sensors confirm it's true. The bit about Vulcans being overconfident because they've never been conquered seems inconsistant with their portrayal as a wise, space-faring race. Kirk and the gang certainly encounter enough large, powerful beings to keep them humble! The ameoba doesn't scare Spock so much as excite him, as it does McCoy. These guys are ever seeking an opportunity for adventure, and competition. But Bones does wish his fellow officer luck, and their grudging mutual respect is undeniable.