Season 2 started off quite well with "Chapter 1: Madmax", though it was also a bit of a let down after a strong first season. It served its purpose of setting things up for what's to come and introducing the chess pieces well, as well as progressing characterisation, but struck me as a little too slow and thinly plotted. But often good but not great or less season openers are followed by a big improvement in quality, so expectations were high for "Chapter Two: Trick or Treat Freak".
"Chapter Two: Trick or Treat Freak" is far from perfect and showed that there was still some way to go. It however is a better episode as it does very well on building upon what was introduced in "Madmax" and progressing it. On the whole quality-wise "Chapter Two: Trick or Treat Freak" is a very good episode, though not a Season 2 high point and nowhere near the standard of the best of Season 1 (the best being outstanding and true of about half the season).
It is still a little slow at times, especially in the taking too long to set up early portions. Other episodes have more suspense and surprises too.
However, there are a lot of things that "Chapter Two: Trick or Trick Freak" does between extremely well and brilliantly. 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 when things get going in the final act and also some breathing space also when needed.
Furthermore, the brains and heart present in all the previous episodes of 'Stranger Things' are here and very strongly. It's also less melodramatic than some episodes of the show. The story is at least coherent and while a long way from perfect in momentum it is not a tonal muddle, has some intrigue and some tension towards the end. There is more plot progression than in "Madmax" too. 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').
Very good episode that indicates a lot of potential for Season 2. 8/10.