What a way to start the third broadcast season.
In the 1970s, official fandom such as Gerrold, also Marshak & Culbreath, would refer to this with some anger. They thought "NBC's decision" to air Spock's Brain first was an insult, a reflection of how little respect NBC had for Star Trek
They seemed unaware of the fact that NBC did not write or produce Spock's Brain, and the network had to run the episode that was ready first, the one whose music and fx were finished and final print was delivered.
Anyway, I like this episode. It's a fun outing with superb original music, hot women, great fight scenes, and Shatner in top form as Kirk.