Someone is killing patients at Boston Memorial, and the reasons are confusing - but two people are close to realizing that something is going on, so the killer must act. One, Cassi Kingsley, is a former pathology resident who has switched to psychiatry, and the other is her friend Robert, who is still in pathology. They've noticed a pattern in deaths that don't have proper explanations. Cassi's husband, Thomas, is a superstar of the cardiology ward, and a surgeon of top class - he wants her to stop, as if these deaths have a medical reason, it will bring down the hospital. And the murderer wants these investigations to stop as well, for obvious reasons.
