Addison is no stranger to feeling stressed, insecure, and sad. Her therapist recommended she keep a journal to help her understand those feelings better, which she really needs today. It's her first day back to school, several weeks after she survived her suicide attempt. She knows there are rumors about why she did it: A lousy home life? Bullying? Heartbreak? None of them are true, but it doesn't matter because Addison still feels like she's drowning. She still holds secrets she's not ready to share.

During the school day, Addison encounters four other students struggling with their own secrets:

Booker is anxious about seeing Addison. They were sort of a couple until he tried to kiss her. She fled and then tried to end her life. Those two things couldn't be related, could they?

Celia feels trapped by her mother's abusive boyfriend. She can guess why Addison did what she did.

Damion is TikTok-famous and thinks befriending Addison could boost his followers. But what no one knows is he needs the world to remember him since his sick mom doesn't anymore.

Avery is considered a loner and doesn't know Addison, but they have neighboring lockers. With Avery's older brother in jail for dealing drugs, Avery is desperate for meaningful human connection.

Swimming in a Sea of Stars is a poignant and gripping novel about how we're all interconnected, like the stars in the night sky that form constellations and map out the universe, and if even one star goes missing, the effect is profound.