Jack the Ripper was renowned artist Walter Sickert (1860-1942) according to Cornwell, in case anyone hasn't yet heard. The evidence Cornwell accumulates toward that conclusion in this brilliant, personal, gripping book is very strong, and will persuade many. In May 2001, Cornwell took a tour of Scotland Yard that interested her in the Ripper case, and in Sickert as a suspect. A look at Sickert's "violent" paintings sealed her interest, and she became determined to apply, for the first time ever, modern investigatory and forensic techniques to the crimes that horrified London more than 100 years ago. The book's narrative is complex, as Cornwell details her emotional involvement in the case; re-creates life in Victorian times, particularly in the late 1880s, and especially the cruel existence of the London poor; offers expertly observed scenarios of how, based on the evidence, the killings occurred and the subsequent investigations were conducted; explains what was found by the team of experts she hired; and gives a psycho-biography of Sickert. The book is filled with newsworthy revelations, including the successful use of DNA analysis to establish a link between an envelope mailed by the Ripper and two envelopes used by Sickert. There are also powerful comparisons made between Sickert's drawing style and that of the Ripper; between words and turns of phrases used by both men; and much other circumstantial evidence. Also newsworthy is Cornwell's conclusion that Sickert continued to kill long after the Ripper supposedly lay down his blade, reaping dozens of victims over his long life. Compassionate, intense, superbly argued, fluidly written and impossible to put down, this is the finest and most important true-crime book to date of the 21st century.