Bele and Lokai from Charon take their personal struggle aboard the Enterprise.
Here is an episode I wanted to like, a serious 20th century problem transposed into the 23rd century but it's mainly swallowed by 3rd season "Star Trek formula". The set-up is good, blind and ultimately silly racial hatred coming to bear at one point in time. There are an awful lot of similarities to Dr. Suess's tale of "Sneeches", but still. Lokai has some good scenes preaching in the recreation room, Bele has some nasty and pointed dialog as well.
But all this is obliterated in a poorly-reasoned script and meandering direction. Why is the Federation, familiar with the protagonists' homeworld at the "southern" end of the galaxy unaware of its complete destruction long ago? Why are beings as powerful as Bele and Lokai (able to drive ships with their mind and generate force fields with their bodies) bothering to follow any ship's rules? The back-and-forth direction of the ship's heading needlessly takes away from the main point of the entire show - almost as if any deeper examination of the real issue would be too much.
Though somewhat progressive in its topic for the 1960s, there is just not enough real follow-up in the execution here.