She is a young professional woman with a stable job and a promising future. Cahalan, however, for unknown reasons begins to experience symptoms – sensitivity to light, mood swings, slight hallucinations, speech impediments among others that she can’t explain. After seeing a doctor about this initially, she is told it is due to excessive partying; alcohol withdrawals. One of her doctors speculates that what Cahalan is experiencing are caused by her birth control, still another believes these symptoms are the result of too much stress.