Summary: The kids figure out that Will is in another dimension and try to figure out how to get into it. They attempt to locate a portal, but their attempts are subverted by El. Lucas gets in a fight with Dustin and Mike and leaves and El runs away. Nancy and Jonathan go hunting for the monster and Nancy finds a portal to the other dimension where she sees the monster. Lonnie returns to see Joyce only for the money and tries to shut down her efforts to contact Will. Hopper continues to investigate Hawkins Lab but they are aware of him and attempt to monitor his movements.
The Good: This was a much stronger effort and it is my favourite episode since the pilot.
Hopper's investigation was very fun as usual but I think this was the best episode of it. The opening sequence was very tense and while it was cliché at times like with Hopper taking care of the guards, I did enjoy it a lot more because there was a lot of suspense and we weren't sure how much Hopper would uncover about the lab. I also loved the scene with Hopper hunting for the wiretap, it was the smartest that show has been with this investigation and it was nice to see some thought put into the show and the characters.
The kid storyline was superb in this episode with some real conflict and plot progression. I really love their interactions which remain as fun and special as ever. The conflict and fight at the end also felt earned since we have seen some hostilities forming between the trio ever since Eleven was introduced and the writers did an excellent job of staging this scene to feel like the big breaking point between all of the friends.
The best thing about that scene was how everyone's motivations felt real. Lucas wants to find Will and is angry at El's betrayal, Mike is upset that Lucas has been so hostile towards El and Dustin is just trying to keep everything calm. But better than this is El's motivation to prevent them from finding the portal. She knows it will take them to Hawkins Lab and she is afraid of going back there. After seeing so many flashbacks of her former life it's completely believable that she has been traumatized by her past and her tears and panic at the end feel very real and felt like an organic next step in the story. I will applaud the writers for doing a great job with the kids storyline which has been the most consistently well written so far.
The Nancy/Jonathan story was very good in this episode too. It makes sense that they wouldn't be too fond of each other considering who they are, and I'm very glad to see that they didn't just split up after their argument. Though they may not be friends, they only have each other in the hunt for Barb and Will, which makes it realistic for them to stick together. The final scene was also very tense and exciting and it's good to see the monster for the first time. I'm also surprised to see that Nancy has entered the other dimension and I wonder if she is gone now too (see: The Unknown).
I liked the scene between Steve and Nancy too. It's nice to see that Steve isn't being painted as just some stupid and selfish teenager but actually a somewhat decent guy.
The Bad: The usual of course. The show is too clichéd still despite a few surprising developments which make it less predictable.
Lonnie's return was tedious and felt mostly pointless. It didn't further any storylines, wasn't interesting and was overall just a pointless roadblock which would prevent Jonathan from talking to Joyce about the monster before the plot wants it to happen.
The final scene was tense and exciting but had some major issues. The monster just taking the dead prey and ignoring both Nancy and Jonathan was really dumb and didn't seem to make any sense. We need a better idea of why the monster attacks people soon. I didn't like that Nancy just stupidly went into the mysterious hole without getting Jonathan. Surely she would want to tell him where she is going in case something bad happens. And it was beyond ridiculous that Jonathan didn't hear Nancy calling him over but heard her getting attacked.
The Unknown: A couple questions.
Why does the monster kill? How does it enter the regular world at will? Why was it not interested in Nancy and Jonathan at first?
Why did the Hawkins Lab leave Hopper alive and on his own? Are they watching him? Do they have a special plan for him? What else will Hopper tell Joyce and will they work together now?
Will Lonnie come back later in the story?
Best Moment: The big scene between the kids where they fought at the end was tense and wonderful. A perfect culmination for tons of build up.
Character of the Episode: Tough to choose in this episode. In the end I will pick Eleven over Hopper by a hair because I thought the story had built so well to that climax and El was the standout in that scene. Hopper wasn't quite as impressive.
Conclusion: This was much better. The writing and storytelling improved quite a bit and made for a really enjoyable episode. This is a much brighter sign for the final 3 episodes which can hopefully live up to expectations.