12-year-old Mysti Murphy wishes she was a character in a book. If her life was fictional, she'd magically know how to deal with the fact that her best friend, Anibal Gomez, no longer wants to talk to her during school hours. She'd be able to take care of her family when her dad has to spend time in the hospital. And she'd certainly be able to change the secret fact about her family: her mother is agoraphobic and never leaves the house. School used to be the only escape for Mysti, but now that Anibal is trying to make friends with the popular crowd, Mysti is left alone at 'Loser Island' - the cafeteria table with misfits. At first Mysti can't stand the other kids there: know-it-all Wayne Kovok and standoffish new girl Rama Khan. But as Anibal changes for the worse, Mysti realises being a 'secret friend' is no kind of friend at all - and Rama and Wayne might understand her better than she thought.
Ultimately, Mysti begins to see that her mother is afraid of everything, but Mysti can be brave in little ways even if she's not a character in a book: by standing up to Anibal when he's bullying her, by walking to the grocery store on her own when her mother can't leave the house, or by visiting her father at the hospital. And bit by bit, Mysti realises she's not alone after all.