Shatner's favorite episode. One of mine as well. Sad to think that during the filming of this, Shatner's father died suddenly in Florida.
Tightly plotted, good social commentary, some humor. But I will say that boy, o boy, were "special effects" primitive back then. The Horta looks like an area rug with melted plastic on it (because that is probably what it is!). As good as the writing and acting (and directing) is, one has to wonder how much better the show could have been if it had ever been given the budget it deserved. Yeah, yeah, hindsight is 20/20 and it never had the ratings etc, but still...