Aluna and her people live under the waves in the City of Shifting Tides. Their breathing necklaces start to fail so Aluna and her friend, Hoku, journey to the Above World so they can find a way to save their people. They encounter other worlds like the Aviars, who have wings and live in a mountain, and the Equians, who are like centaurs. They discover that other people are having trouble too.
This book falls into the dystopian sci-fi category.
I would recommend this book to girls and boys in middle-school ages and older, and also anyone fascinated by water. I really liked that each chapter is from a different character's point of view. It felt like I was in that world; and the vocabulary was easy to understand. I learned that even people who are different and come from different worlds can get along.
The ending was so suspenseful, I can't wait to read the next book. I can't think of anything I didn't like about it.
I really liked this book; it is the best book I've ever read!