This story is a work of fiction, but its background is authentic and its premise frighteningly plausible. It involved copious amounts of research in which I received invaluable help from the following people, all of whom gave their time and expertise with a willingness and generosity for which I will always be grateful: Dr. Richard H. Ward, Professor of Criminology and Associate Chancellor of the University of Illinois, Chicago; Professor Joe Cummins, Emeritus of Genetics, University of Western Ontario; Zhenxiong “Joe” Zhou, Office of International Criminal Justice, Chicago; Professor Dai Yisheng, former Director of the Fourth Chinese Institute for the Formulation of Police Policy, Beijing; Professor He Jiahong, Doctor of Juridical Science and Professor of Law, People’s University of China School of Law; Professor Yijun Pi, Vice Director of the Institute of Legal Sociology and Juvenile Delinquency, China University of Political Science and Law; Professor Wang Dazhong, Director of the Criminal Investigation Department, Chinese People’s Public Security University; Mr. Chen Jun, Secretary-General of the Eastern Film and TV Production Centre, Beijing; Police Commissioner Wu He Ping, Ministry of Public Security, Beijing; Steven C. Campman, MD, Forensic Pathology Fellow, Northern California Forensic Pathology; Robert D Cardiff, MD, PhD, Professor of Pathology, University of California, Davis, School of Medicine; Kevin Sinclair, writer and journalist, South China Morning Post; Liu Xu and his mother Shimei Jiang who were my tireless sherpas in Beijing.

I could not complete a list of credits without mentioning the biggest contributer of all—the Internet. Without it I would not have made contact with many of those who helped and advised. Nor would it have been possible to access so quickly and freely the information I required to build a detailed and authentic background to my story.