i thought the concept of this book was really good. i found their world fascinating which is set underwater and i wanted to experience it muself so i really loved that. 
 Evelyn was fine but i didnt feel particularly anything for her. She was kinda boring to be honest. Gavin was ok too - more likable than her for sure. Their romance felt kinda too soon for me and i liked them together bit didnt care that much about it. It didnt make me swoon or anything. 
 The plot mostly revolves around them trying to escape that world and go to the surface. It was good with some twists that kept you hooked. I absolutely hated the Mother. She was proper messed up in the head and i just wanted to kill her but i think she was a good villain. 
 Overall, i love dystopian books so liked this one as well. I think the sequel will be quite interesting, getting to see a different sid eof their universe.