Season 1 was a very good, and at its best excellent, start to one of Netflix's better shows, was not expecting 'Stranger Things' to be a hit but it did turn out to be that. Although a couple of episodes weren't as strong as the others, none of the eight episodes that made the season up were less than decent and the best of them were outstanding. "Chapter Six: The Monster" does sound very interesting from the plot synopsis despite risking the possible danger of being over-stuffed and melodramatic.
Everybody is undoubtedly going to have their pick for their least favourite episode of Season 1. "Chapter Six: The Monster", while still liking it and finding a lot great about it, is my pick. Of the previous five episodes, it would have been "Chapter Two: The Weirdo on Maple Street", also still good. Will reiterate that saying that is not because "Chapter Six: The Monster" is bad, it's only because four of the previous five episodes are so great.
Those episodes, as did "Chapter Two: The Weirdo on Maple Street", fared better at progressing events and introducing other plot strands. "Chapter Six: The Monster" has been described by some as a filler episode and it is not hard to see why. It did progress the characters and their relationships, especially Nancy and Jonathan, but the momentum is not always there due to that there are distractions that get in the way too much. Not an awful lot here that is much different to what has already been covered.
Did feel that some of "Chapter Six: The Monster" was at times on the melodramatic and contrived side. Do completely agree with everyone that found everything with the bullies particularly forced and too shoehorned, plus with too much over-reliance on coincidence. This aspect could have been left out completely and it would have not harmed the episode at all, and it would have meant that the episode could spend more time with the main plot.
However, despite saying all of that (which does seem to indicate that it is bad when it has already been said twice that it's not), a lot in "Chapter Six: The Monster" is done very well. The production values are typically very stylish and atmospheric, with some beautiful and unsettling images. The music is suitably haunting and nostalgic and the direction does well in creating enough tension when needed and also some breathing space also when needed.
Despite some melodramatic and forced moments, the usual brains and heart quality is present in the writing with some welcome levity when needed. The story is at least coherent and while a long way from perfect it is not a tonal muddle, has intrigue and some tension towards the end. The character writing advances a good deal all round and the characters don't bore or frustrate. The acting is very good, with the younger cast faring better than the older ones (found this in a lot of episodes of 'Stranger Things').
Overall, good but not great. 7/10.