This book is meant to be a prequel to the City of Ember but, honestly, feels like it should have been a standalone book. At the end, some things tie up and we find out some links back to the City of Ember but most of this book felt very random.

I highly suggest skipping this in the series, or just reading the last chapter of what happens after. Otis was cute (a dog) and I enjoyed the links back to ember at the end and how a couple things tied up but it felt like a completely different book for 99% of the time.