 Forensic pathologist Dr. Sam Ryan returns to Cambridge to take up a teaching assignment and to work for the police as required. In her first case, she has to deal with the death of a six year old girl find floating in a nearby river. The autopsy reveals that the child has suffered previous abuse, including cigarette burns and several broken ribs. Sam receives information from a prison inmate that implicates someone in a previous death and Sam suggests a radical step. In her personal life, Sam has to deal with her elderly mother who is showing signs of dementia and her sister Wyn with whom she has a strained relationship.