In this follow-up to 2002's Portrait of a Killer: Jack the Ripper, Case Closed, Cornwell doggedly clings to her accusation that the legendary serial killer was painter Walter Sickert, though she concedes that her original case was overstated. However, in this account she does little to remedy the holes left in the last. Cornwell still imputes significance to facts of dubious relevance-for example, she links the uncommon use of "ha ha" in Ripper's letters to Sickert through his friendship with James McNeill Whistler, who was known for saying "ha ha." Her account jumps around chronologically, which makes ill-suited to readers who are unfamiliar with the case. She includes a section responding to critics of her prior book, as well as a litany of bizarre occurrences that she attributes to the Ripper's lingering psychic presence ("From the first moment I began this work, I sensed an entity, a terrifically negative energy that when invoked causes strange aberrations of physics"). At one point, she oddly claims that she chose not to interview a previous author who'd suspected Sickert, though that writer had died 16 years before she began her quest. Even readers willing to put her idiosyncrasies aside will find that after so much time and effort, Cornwell still fails to present convincing proof of her theory. Color illus. (Jan.) © Copyright PWxyz, LLC. All rights reserved.