This muddled story starts engagingly enough. Chris Cole wants to run the Boston Marathon unofficially and the way looks clear. The high-spirited, healthy 17-year-old is being coached by Skip Malone, age 20, ""the best young distance runner in New England""--who is secretly rich, wants to be a writer like Chris' boozing-novelist father, and loves her enough to propose marriage. Why Chris doesn't run the Marathon is the turning point in an increasingly wobbly plot. Days before the race, she is struck down by lupus erythematosus, a disease of the connective tissue. The doctors stress that the course of the illness is unpredictable. Even so, nothing prepares the stunned reader for the bafflingly sudden scene in which Chris, seemingly in remission and looking forward to the future with Skip, wakes up in a fever, hallucinating--and jumps through a closed window of the hospital. She dies right then, and the novel goes down with her.