Lisa Shilling starts off as any normal teenager, attending school, going out with friends, and even dating. As the novel progresses, Lisa slips into dark, depressive moods on occasional days, and then into depression altogether. Lisa's friends notice her change and take it into their own hands to give her "therapy" because Lisa's parents are not willing to accept her sickness. As the depression progresses, many frightening incidents happen, but Lisa's friends stick with her, helping to give strength to Lisa as well as themselves.
Lisa's friends stick with her when no one else will. One incident happened where Lisa went into an almost trance-like episode and then proceeded to attack one of her three friends. Even through the difficult times, Lisa's friends would not give up on her. The basic theme of friendship is expressed throughout the novel.
It is never told exactly what has caused Lisa Shilling to slip into this state of depression, which helps to make the atmosphere of the novel very mysterious. Just when it appears that Lisa is getting better, another episode occurs. The story is disturbing, being set around Lisa's school and home. With other characters in the story, such as Lisa's parents, causing conflicts with Lisa receiving proper treatment, the story is given a disturbing yet realistic feel.
Instead of the story being told from the main character's point of view, it is instead told by one of Lisa's three friends who is trying to help. This keeps the