Despite advances in DNA evidence and forensic analysis, almost half of murder cases in Canada and the US remain unsolved. By 2016, the solved rate had dropped so significantly in the United States that it was the lowest in recorded history, with one in two killers never even identified, much less arrested and successfully prosecuted. And the statistics are just as bad in Canada. As a sought-after global expert and former detective, Arntfield has devoted his career to helping solve cold cases and serial murders, including the creation of the Western University Cold Case Society, which pairs students with police detectives to help solve crimes. In , Arntfield outlines the history of cold case squads in Canada and the US, and lays out the steps to understanding and solving crime. Arntfield shows you what to look for, how to avoid common mistakes, recognize patterns and discover what others have missed. Weaving in case studies of cold crimes from across Canada and the US, as well as a chapter on how armchair detectives can get involved, is a must-read for mystery fans and true crime buffs everywhere.