In January 1889, as London constables hunted for Jack the Ripper and theaters around the world presented theatrical renditions of the Jekyll and Hyde story, Jackson, Michigan, Police Captain Jack Boyle searched for the murderer of Mary Latimer. This book follows Captain Boyle to the bordellos of gaslight-era Detroit-populated by madams, pimps, prostitutes and gamblers. It describes the investigation that led him to a pharmacist that prowled the streets, akin to a real-life Jekyll and Hyde. Ultimately, the book delves into the mind of Robert Irving Latimer, known as the most dangerous prisoner in Michigan and the man who inspired talk about resurrecting the state's long-dead death penalty.