The Upside Down is one of the best season finales and I put it up there with some of the other shows best season finales (Game of Thrones, Breaking Bad, Once Upon A Time, etc, etc.) Not only does it provide some great character depth including fleshing out Steve, the bully introduced in the beginning of season 1 now realizing the way he treated Jonathan and the others and decides to help the others defeat the DemoGorgon, but it wraps up everything else the first season established. There's also a cliffhanger (which I won't spoil to those who haven't seen the show yet) which might leave you interested. The story continues to be well-written providing an emotional punch to the climax where Eleven sacrifices herself to defeat the DemoGorgon and save Mike and the others while Hopper and Joyce save Will from the Upside Down. The pacing is great, the music score and production design continue to compliment the 1980s setting respectfully, the effects are great, and the acting from everyone involved is great with Millie Bobby Brown, David Harbour, Winona Ryder, and Finn Wolfhard giving the best performances as did the other two who played Lucas and Dustin who shared some funny moments throughout the whole season. Overall, The Upside Down is a perfect season finale. Recommended. :)