The episode opens, as many do, with the Quest team responding to a desperate plea for help. We see here the optimism of science, how Dr. Quest will put his towering intellect to work making the world a better place. It is nicely contrasted against the episode's central theme, which is that science, while impersonal, can be misused or used carelessly, often with dire consequences. Dr. Quest's triumph, and sad coda commenting on Dr. Norman, suggest that while science sometimes causes problems, it more often solves those problems. This is an optimism now largely gone from the world.
Effects are first rate, from the hideous "eye" of the eventually revealed monster, to its weird ululating cry. And as is usually the case, the trademark Quest music adds to the feel and tone.
The episode has a few inconsistencies, mostly pointed out on the trivia page, that detract from it just enough to make it merely excellent, instead of flawless.