My thanks for help in writing this book must go first and foremost to my wife, Carol, whose photographs, copy-editing and all-round enthusiasm are, as always, invaluable. To Rupert Harding and his team at Pen and Sword, for meeting impossible deadlines. To Elliot McCaffrey and his team at Atlantic Productions for their faith in me. To Professor Laurence Alison, Director of the Centre for Critical and Major Incident Research, University of Liverpool; Spencer Chainey of the Jill Dando Institute, University College London; Alan Humphries, Librarian of the Thackray Museum, Leeds and Dr Peter Dean, Coroner for Suffolk and South East Essex, for their professionalism and insight; and to Ripper expert John Bennett for his profound knowledge of Jack’s killing fields.