Instruct: Classify Amazon reviews into positive or negative sentiment
Query: hidden gem

I have had this book on my shelf for at least two years before I thought to read it- what a mistake! I thought it looked interesting when I picked it up, but never found the time to start it. A couple days ago I finally chose this book to read. I could hardly put it down! I found myself rooting for Dora and Miss B and angered by those against her, especially--Dr G Thomas and Brady Ketch. It was a great read and left me longing for more of Dora and her allies.