There's a killer on the loose in Boston; a killer who targets lone women, breaks into their apartments in the early hours of the morning, and performs bizarre and ritualistic acts of torture on his victims before finishing them off.His surgical skills lead police to suspect he is a physician who works alongside unsuspecting doctors and nurses at the Pilgrim Medical Center, a physician who, instead of saving lives, takes them in the most terrifying of ways.But as soon as homicide detective Thomas Moore and his partner Jane Rizzoli begin their investigation, they make a startling discovery. Closely linked to these killings is Catherine Cordell, a beautiful medic with a mysterious past. Two years ago, she was the subject of a horrifying rape and attempted murder, but shot her aggressor dead. Now she is being targeted by this new killer who seems to know all about her past, her work at the Medical Center and, crucially, where she lives. The man she believes she killed now seems to be stalking her once again, only this time he knows exactly where to find her, and nowhere - whether it is the ER, the squad room, the city morgue or even her apartment - is safe. ..