"Notes from the Upside Down: An Unofficial Guide to Stranger Things" by Guy Adams is a 240-page trade paperback published in 2017 by Touchstone. It serves as a comprehensive reference guide to the popular TV series Stranger Things, providing in-depth analysis and insights into the show's characters, plotlines, and themes. Written in English, this book is a must-have for fans looking to deepen their understanding of the series and explore the mysteries of the Upside Down.