Teenager Zibby Lloyd must complete inpatient treatment for her bulimia, and her psychiatrist wants her to keep a diary while she's there. Zibby doesn't think she belongs in treatment, but the other patients at Hope House don't seem to agree. Soon, Zibby learns she's getting a new roommate, and it's someone she never expected to see. Will the new girl, Lauren, help Zibby recover—or become her worst enemy?