Overview
Atlantia is a young adult novel authored by Allyson Braithwaite Condie. The novel is a Library of Congress Cataloging-In-Publication. The cover photo for the hardcover edition is by C&P. The story is told from the perspective of Rio, a girl from the underwater city of Atlantia. This novel is recommended for ages 12 and up, and is a New York Times bestseller.
Plot
The story begins when Rio attends the ceremony of the Divide. Initially, Rio wants to go aboveground, but she has promised her Below-loving twin sister, Bay, to remain in Atlantia, an artificial city built entirely underwater.
Rio completed the ritual before Bay, choosing to stay below, but Bay surprised Rio by choosing to go Above. In a panic, Rio accidentally revealed the siren voice she had hidden since birth to a priest, risking arrest, but she was able to leave without issue.
Rio searched desperately for an explanation for Bay's choice, eventually meeting her siren aunt, Maire, whom she last saw at her mother's funeral, and running away due to being engulfed in the memories of her late mother, Oceana. As she wept, she met True Beck, a boy whose best friend departed similarly to Bay, seeking a partner with whom to solve these mysteries Rio rejected his offer, and when she changed her mind, True was gone.
From Wikipedia (CC BY-SA 4.0).