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NBC and Desilu Studios determined the initial episode ordering based on what they believed would attract viewers into sticking with the series, similar to how a book needs to have a catchy opening or else it will lose readers. Because of that, "The Man Trap" and "Charlie X" were aired before "Where No Man Has Gone Before," causing very noticeable continuity differences such as uniform styles, crew positions, and especially Spock's emotions seen in "Where No Man Has Gone Before."