Real sign-o-the-times:a series that had its share of corruption on the police force, which was not common on regular police TV series, even at the end of a decade where charges (and a wealth of evidence) of police abuse was a serious, widespread matter in the U.S. More on the actor who guest starred as Jerry than Lipton, as she was usually a cooler performer. Scotty gets a genuine romance. That made the episode, and there's more world (galaxy) building with the introduction and purpose of Memory Alpha--library of the Federation. Considering the episode's theme or a crewmember being taken over by an external, alien force, many tracks from Alexander Courage's score for "Where No Man Has Gone Before" was put to effective use throughout the episode. Kirk's joking "Can I stand the strain?" comment about his friends being in (rare) complete agreement was a nice, "Awww" way to end the episode. Chuck Cramer was portrayed by the versatile Charles Bateman, who will return to bedevil Max and the gang one season later as the KAOS ape-turned-man "Chucko"/Agent Chuck Armstrong in "The Apes of Rath" (CBS, 11/28/69).