Love this one. The framing story is wonderfully detailed and executed. In an era when just sitting around and reminiscing would be an excuse for a clip show (or in the case of Irwin Allen, just writing in the stock footage), great care of taken to show how this story fit into Trek’s continuity and how it was STILL a story about Kirk – even though Kirk didn’t exist when The Cage was filmed.
Easily my favorite exchange in the episode, if not the series, is between Kirk and Bones about suspecting Spock. The music choices and the actors’ performances are top grade. McCoy, for the first time, sides with Spock and is totally wrong. Kirk won’t let his friendship with the Vulcan color his judgment, which is a great piece of characterization. Often, when this episode was rerun in my market, it was a big deal. “See Star Trek’s only two part episode! At a special time! The Menagerie on 11 Alive!”
Plot holes? Sure. Great entertainment? Absolutely! A solid 9.