It was the biggest, most costly hoax of the 20th century, the results of which were wasted lives, money and police resources. In the midst of the hunt for the Yorkshire Ripper, police were thrown off the scent by an elaborate hoax. Letters and tapes sent to the police contained information they claimed could only be known by the serial killer himself and led them to a costly conclusion: that the hoaxer and the Ripper were one and the same. This book examines the massive police hunt for the man who became known as "Wearside Jack". It reveals the various theories about the identity of Wearside Jack, his probable motive for the hoax and the unusual series of events that took police away from the trail of arguably Britain's worst serial killer.